diff --git a/ext/infix_iterator.h b/ext/infix_iterator.h deleted file mode 100644 index 519b338..0000000 --- a/ext/infix_iterator.h +++ /dev/null @@ -1,57 +0,0 @@ -// -// Created by mwo on 24/05/15. -// -// source: http://codereview.stackexchange.com/questions/13176/infix-iterator-code - -// infix_iterator.h -#if !defined(INFIX_ITERATOR_H_) -#define INFIX_ITERATOR_H_ -#include -#include -#include - -template > -class infix_ostream_iterator : - public std::iterator -{ - std::basic_ostream *os; - std::basic_string delimiter; - std::basic_string real_delim; - -public: - - typedef charT char_type; - typedef traits traits_type; - typedef std::basic_ostream ostream_type; - - infix_ostream_iterator(ostream_type &s) - : os(&s) - {} - - infix_ostream_iterator(ostream_type &s, charT const *d) - : os(&s), - real_delim(d) - {} - - infix_ostream_iterator &operator=(T const &item) - { - *os << delimiter << item; - delimiter = real_delim; - return *this; - } - - infix_ostream_iterator &operator*() { - return *this; - } - - infix_ostream_iterator &operator++() { - return *this; - } - - infix_ostream_iterator &operator++(int) { - return *this; - } -}; - -#endif - diff --git a/ext/json.hpp b/ext/json.hpp index 432f9d0..9c27fb0 100644 --- a/ext/json.hpp +++ b/ext/json.hpp @@ -1,11 +1,11 @@ /* __ _____ _____ _____ __| | __| | | | JSON for Modern C++ -| | |__ | | | | | | version 2.0.7 +| | |__ | | | | | | version 2.1.1 |_____|_____|_____|_|___| https://github.com/nlohmann/json Licensed under the MIT License . -Copyright (c) 2013-2016 Niels Lohmann . +Copyright (c) 2013-2017 Niels Lohmann . Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal @@ -29,42 +29,40 @@ SOFTWARE. #ifndef NLOHMANN_JSON_HPP #define NLOHMANN_JSON_HPP -#include // all_of, for_each, transform +#include // all_of, copy, fill, find, for_each, none_of, remove, reverse, transform #include // array #include // assert -#include // isdigit #include // and, not, or -#include // isfinite, signbit +#include // lconv, localeconv +#include // isfinite, labs, ldexp, signbit #include // nullptr_t, ptrdiff_t, size_t #include // int64_t, uint64_t -#include // strtod, strtof, strtold, strtoul -#include // strlen +#include // abort, strtod, strtof, strtold, strtoul, strtoll, strtoull +#include // memcpy, strlen +#include // forward_list #include // function, hash, less #include // initializer_list -#include // setw +#include // hex #include // istream, ostream -#include // advance, begin, bidirectional_iterator_tag, distance, end, inserter, iterator, iterator_traits, next, random_access_iterator_tag, reverse_iterator +#include // advance, begin, back_inserter, bidirectional_iterator_tag, distance, end, inserter, iterator, iterator_traits, next, random_access_iterator_tag, reverse_iterator #include // numeric_limits #include // locale #include // map #include // addressof, allocator, allocator_traits, unique_ptr #include // accumulate #include // stringstream -#include // domain_error, invalid_argument, out_of_range #include // getline, stoi, string, to_string -#include // add_pointer, enable_if, is_arithmetic, is_base_of, is_const, is_constructible, is_convertible, is_floating_point, is_integral, is_nothrow_move_assignable, std::is_nothrow_move_constructible, std::is_pointer, std::is_reference, std::is_same, remove_const, remove_pointer, remove_reference +#include // add_pointer, conditional, decay, enable_if, false_type, integral_constant, is_arithmetic, is_base_of, is_const, is_constructible, is_convertible, is_default_constructible, is_enum, is_floating_point, is_integral, is_nothrow_move_assignable, is_nothrow_move_constructible, is_pointer, is_reference, is_same, is_scalar, is_signed, remove_const, remove_cv, remove_pointer, remove_reference, true_type, underlying_type #include // declval, forward, make_pair, move, pair, swap #include // vector // exclude unsupported compilers #if defined(__clang__) - #define CLANG_VERSION (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__) - #if CLANG_VERSION < 30400 + #if (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__) < 30400 #error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers" #endif #elif defined(__GNUC__) - #define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) - #if GCC_VERSION < 40900 + #if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) < 40900 #error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers" #endif #endif @@ -75,6 +73,12 @@ SOFTWARE. #pragma GCC diagnostic ignored "-Wfloat-equal" #endif +// disable documentation warnings on clang +#if defined(__clang__) + #pragma GCC diagnostic push + #pragma GCC diagnostic ignored "-Wdocumentation" +#endif + // allow for portable deprecation warnings #if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__) #define JSON_DEPRECATED __attribute__((deprecated)) @@ -84,6 +88,26 @@ SOFTWARE. #define JSON_DEPRECATED #endif +// allow to disable exceptions +#if (defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND)) && not defined(JSON_NOEXCEPTION) + #define JSON_THROW(exception) throw exception + #define JSON_TRY try + #define JSON_CATCH(exception) catch(exception) +#else + #define JSON_THROW(exception) std::abort() + #define JSON_TRY if(true) + #define JSON_CATCH(exception) if(false) +#endif + +// manual branch prediction +#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__) + #define JSON_LIKELY(x) __builtin_expect(!!(x), 1) + #define JSON_UNLIKELY(x) __builtin_expect(!!(x), 0) +#else + #define JSON_LIKELY(x) x + #define JSON_UNLIKELY(x) x +#endif + /*! @brief namespace for Niels Lohmann @see https://github.com/nlohmann @@ -92,660 +116,1789 @@ SOFTWARE. namespace nlohmann { - /*! @brief unnamed namespace with internal helper functions -@since version 1.0.0 + +This namespace collects some functions that could not be defined inside the +@ref basic_json class. + +@since version 2.1.0 */ -namespace +namespace detail { +//////////////// +// exceptions // +//////////////// + /*! -@brief Helper to determine whether there's a key_type for T. +@brief general exception of the @ref basic_json class -Thus helper is used to tell associative containers apart from other containers -such as sequence containers. For instance, `std::map` passes the test as it -contains a `mapped_type`, whereas `std::vector` fails the test. +Extension of std::exception objects with a member @a id for exception ids. -@sa http://stackoverflow.com/a/7728728/266378 -@since version 1.0.0, overworked in version 2.0.6 +@note To have nothrow-copy-constructible exceptions, we internally use + std::runtime_error which can cope with arbitrary-length error messages. + Intermediate strings are built with static functions and then passed to + the actual constructor. + +@since version 3.0.0 */ -template -struct has_mapped_type +class exception : public std::exception { + public: + /// returns the explanatory string + virtual const char* what() const noexcept override + { + return m.what(); + } + + /// the id of the exception + const int id; + + protected: + exception(int id_, const char* what_arg) + : id(id_), m(what_arg) + {} + + static std::string name(const std::string& ename, int id) + { + return "[json.exception." + ename + "." + std::to_string(id) + "] "; + } + private: - template - static int detect(U&&); + /// an exception object as storage for error messages + std::runtime_error m; +}; - static void detect(...); +/*! +@brief exception indicating a parse error + +This excpetion is thrown by the library when a parse error occurs. Parse +errors can occur during the deserialization of JSON text as well as when +using JSON Patch. + +Member @a byte holds the byte index of the last read character in the input +file. + +@note For an input with n bytes, 1 is the index of the first character + and n+1 is the index of the terminating null byte or the end of + file. This also holds true when reading a byte vector (CBOR or + MessagePack). + +Exceptions have ids 1xx. + +name / id | example massage | description +------------------------------ | --------------- | ------------------------- +json.exception.parse_error.101 | parse error at 2: unexpected end of input; expected string literal | This error indicates a syntax error while deserializing a JSON text. The error message describes that an unexpected token (character) was encountered, and the member @a byte indicates the error position. +json.exception.parse_error.102 | parse error at 14: missing or wrong low surrogate | JSON uses the `\uxxxx` format to describe Unicode characters. Code points above above 0xFFFF are split into two `\uxxxx` entries ("surrogate pairs"). This error indicates that the surrogate pair is incomplete or contains an invalid code point. +json.exception.parse_error.103 | parse error: code points above 0x10FFFF are invalid | Unicode supports code points up to 0x10FFFF. Code points above 0x10FFFF are invalid. +json.exception.parse_error.104 | parse error: JSON patch must be an array of objects | [RFC 6902](https://tools.ietf.org/html/rfc6902) requires a JSON Patch document to be a JSON document that represents an array of objects. +json.exception.parse_error.105 | parse error: operation must have string member 'op' | An operation of a JSON Patch document must contain exactly one "op" member, whose value indicates the operation to perform. Its value must be one of "add", "remove", "replace", "move", "copy", or "test"; other values are errors. +json.exception.parse_error.106 | parse error: array index '01' must not begin with '0' | An array index in a JSON Pointer ([RFC 6901](https://tools.ietf.org/html/rfc6901)) may be `0` or any number wihtout a leading `0`. +json.exception.parse_error.107 | parse error: JSON pointer must be empty or begin with '/' - was: 'foo' | A JSON Pointer must be a Unicode string containing a sequence of zero or more reference tokens, each prefixed by a `/` character. +json.exception.parse_error.108 | parse error: escape character '~' must be followed with '0' or '1' | In a JSON Pointer, only `~0` and `~1` are valid escape sequences. +json.exception.parse_error.109 | parse error: array index 'one' is not a number | A JSON Pointer array index must be a number. +json.exception.parse_error.110 | parse error at 1: cannot read 2 bytes from vector | When parsing CBOR or MessagePack, the byte vector ends before the complete value has been read. +json.exception.parse_error.111 | parse error: bad input stream | Parsing CBOR or MessagePack from an input stream where the [`badbit` or `failbit`](http://en.cppreference.com/w/cpp/io/ios_base/iostate) is set. +json.exception.parse_error.112 | parse error at 1: error reading CBOR; last byte: 0xf8 | Not all types of CBOR or MessagePack are supported. This exception occurs if an unsupported byte was read. +json.exception.parse_error.113 | parse error at 2: expected a CBOR string; last byte: 0x98 | While parsing a map key, a value that is not a string has been read. + +@since version 3.0.0 +*/ +class parse_error : public exception +{ public: - static constexpr bool value = - std::is_integral()))>::value; -}; + /*! + @brief create a parse error exception + @param[in] id the id of the exception + @param[in] byte_ the byte index where the error occured (or 0 if + the position cannot be determined) + @param[in] what_arg the explanatory string + @return parse_error object + */ + static parse_error create(int id, size_t byte_, const std::string& what_arg) + { + std::string w = exception::name("parse_error", id) + "parse error" + + (byte_ != 0 ? (" at " + std::to_string(byte_)) : "") + + ": " + what_arg; + return parse_error(id, byte_, w.c_str()); + } -} + /*! + @brief byte index of the parse error + + The byte index of the last read character in the input file. + + @note For an input with n bytes, 1 is the index of the first character + and n+1 is the index of the terminating null byte or the end of + file. This also holds true when reading a byte vector (CBOR or + MessagePack). + */ + const size_t byte; + + private: + parse_error(int id_, size_t byte_, const char* what_arg) + : exception(id_, what_arg), byte(byte_) + {} +}; /*! -@brief a class to store JSON values +@brief exception indicating errors with iterators + +Exceptions have ids 2xx. + +name / id | example massage | description +----------------------------------- | --------------- | ------------------------- +json.exception.invalid_iterator.201 | iterators are not compatible | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid. +json.exception.invalid_iterator.202 | iterator does not fit current value | In an erase or insert function, the passed iterator @a pos does not belong to the JSON value for which the function was called. It hence does not define a valid position for the deletion/insertion. +json.exception.invalid_iterator.203 | iterators do not fit current value | Either iterator passed to function @ref erase(IteratorType first, IteratorType last) does not belong to the JSON value from which values shall be erased. It hence does not define a valid range to delete values from. +json.exception.invalid_iterator.204 | iterators out of range | When an iterator range for a primitive type (number, boolean, or string) is passed to a constructor or an erase function, this range has to be exactly (@ref begin(), @ref end()), because this is the only way the single stored value is expressed. All other ranges are invalid. +json.exception.invalid_iterator.205 | iterator out of range | When an iterator for a primitive type (number, boolean, or string) is passed to an erase function, the iterator has to be the @ref begin() iterator, because it is the only way to address the stored value. All other iterators are invalid. +json.exception.invalid_iterator.206 | cannot construct with iterators from null | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) belong to a JSON null value and hence to not define a valid range. +json.exception.invalid_iterator.207 | cannot use key() for non-object iterators | The key() member function can only be used on iterators belonging to a JSON object, because other types do not have a concept of a key. +json.exception.invalid_iterator.208 | cannot use operator[] for object iterators | The operator[] to specify a concrete offset cannot be used on iterators belonging to a JSON object, because JSON objects are unordered. +json.exception.invalid_iterator.209 | cannot use offsets with object iterators | The offset operators (+, -, +=, -=) cannot be used on iterators belonging to a JSON object, because JSON objects are unordered. +json.exception.invalid_iterator.210 | iterators do not fit | The iterator range passed to the insert function are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid. +json.exception.invalid_iterator.211 | passed iterators may not belong to container | The iterator range passed to the insert function must not be a subrange of the container to insert to. +json.exception.invalid_iterator.212 | cannot compare iterators of different containers | When two iterators are compared, they must belong to the same container. +json.exception.invalid_iterator.213 | cannot compare order of object iterators | The order of object iterators cannot be compated, because JSON objects are unordered. +json.exception.invalid_iterator.214 | cannot get value | Cannot get value for iterator: Either the iterator belongs to a null value or it is an iterator to a primitive type (number, boolean, or string), but the iterator is different to @ref begin(). + +@since version 3.0.0 +*/ +class invalid_iterator : public exception +{ + public: + static invalid_iterator create(int id, const std::string& what_arg) + { + std::string w = exception::name("invalid_iterator", id) + what_arg; + return invalid_iterator(id, w.c_str()); + } -@tparam ObjectType type for JSON objects (`std::map` by default; will be used -in @ref object_t) -@tparam ArrayType type for JSON arrays (`std::vector` by default; will be used -in @ref array_t) -@tparam StringType type for JSON strings and object keys (`std::string` by -default; will be used in @ref string_t) -@tparam BooleanType type for JSON booleans (`bool` by default; will be used -in @ref boolean_t) -@tparam NumberIntegerType type for JSON integer numbers (`int64_t` by -default; will be used in @ref number_integer_t) -@tparam NumberUnsignedType type for JSON unsigned integer numbers (@c -`uint64_t` by default; will be used in @ref number_unsigned_t) -@tparam NumberFloatType type for JSON floating-point numbers (`double` by -default; will be used in @ref number_float_t) -@tparam AllocatorType type of the allocator to use (`std::allocator` by -default) + private: + invalid_iterator(int id_, const char* what_arg) + : exception(id_, what_arg) + {} +}; -@requirement The class satisfies the following concept requirements: -- Basic - - [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible): - JSON values can be default constructed. The result will be a JSON null value. - - [MoveConstructible](http://en.cppreference.com/w/cpp/concept/MoveConstructible): - A JSON value can be constructed from an rvalue argument. - - [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible): - A JSON value can be copy-constructed from an lvalue expression. - - [MoveAssignable](http://en.cppreference.com/w/cpp/concept/MoveAssignable): - A JSON value van be assigned from an rvalue argument. - - [CopyAssignable](http://en.cppreference.com/w/cpp/concept/CopyAssignable): - A JSON value can be copy-assigned from an lvalue expression. - - [Destructible](http://en.cppreference.com/w/cpp/concept/Destructible): - JSON values can be destructed. -- Layout - - [StandardLayoutType](http://en.cppreference.com/w/cpp/concept/StandardLayoutType): - JSON values have - [standard layout](http://en.cppreference.com/w/cpp/language/data_members#Standard_layout): - All non-static data members are private and standard layout types, the class - has no virtual functions or (virtual) base classes. -- Library-wide - - [EqualityComparable](http://en.cppreference.com/w/cpp/concept/EqualityComparable): - JSON values can be compared with `==`, see @ref - operator==(const_reference,const_reference). - - [LessThanComparable](http://en.cppreference.com/w/cpp/concept/LessThanComparable): - JSON values can be compared with `<`, see @ref - operator<(const_reference,const_reference). - - [Swappable](http://en.cppreference.com/w/cpp/concept/Swappable): - Any JSON lvalue or rvalue of can be swapped with any lvalue or rvalue of - other compatible types, using unqualified function call @ref swap(). - - [NullablePointer](http://en.cppreference.com/w/cpp/concept/NullablePointer): - JSON values can be compared against `std::nullptr_t` objects which are used - to model the `null` value. -- Container - - [Container](http://en.cppreference.com/w/cpp/concept/Container): - JSON values can be used like STL containers and provide iterator access. - - [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer); - JSON values can be used like STL containers and provide reverse iterator - access. +/*! +@brief exception indicating executing a member function with a wrong type + +Exceptions have ids 3xx. + +name / id | example massage | description +----------------------------- | --------------- | ------------------------- +json.exception.type_error.301 | cannot create object from initializer list | To create an object from an initializer list, the initializer list must consist only of a list of pairs whose first element is a string. When this constraint is violated, an array is created instead. +json.exception.type_error.302 | type must be object, but is array | During implicit or explicit value conversion, the JSON type must be compatible to the target type. For instance, a JSON string can only be converted into string types, but not into numbers or boolean types. +json.exception.type_error.303 | incompatible ReferenceType for get_ref, actual type is object | To retrieve a reference to a value stored in a @ref basic_json object with @ref get_ref, the type of the reference must match the value type. For instance, for a JSON array, the @a ReferenceType must be @ref array_t&. +json.exception.type_error.304 | cannot use at() with string | The @ref at() member functions can only be executed for certain JSON types. +json.exception.type_error.305 | cannot use operator[] with string | The @ref operator[] member functions can only be executed for certain JSON types. +json.exception.type_error.306 | cannot use value() with string | The @ref value() member functions can only be executed for certain JSON types. +json.exception.type_error.307 | cannot use erase() with string | The @ref erase() member functions can only be executed for certain JSON types. +json.exception.type_error.308 | cannot use push_back() with string | The @ref push_back() and @ref operator+= member functions can only be executed for certain JSON types. +json.exception.type_error.309 | cannot use insert() with | The @ref insert() member functions can only be executed for certain JSON types. +json.exception.type_error.310 | cannot use swap() with number | The @ref swap() member functions can only be executed for certain JSON types. +json.exception.type_error.311 | cannot use emplace_back() with string | The @ref emplace_back() member function can only be executed for certain JSON types. +json.exception.type_error.313 | invalid value to unflatten | The @ref unflatten function converts an object whose keys are JSON Pointers back into an arbitrary nested JSON value. The JSON Pointers must not overlap, because then the resulting value would not be well defined. +json.exception.type_error.314 | only objects can be unflattened | The @ref unflatten function only works for an object whose keys are JSON Pointers. +json.exception.type_error.315 | values in object must be primitive | The @ref unflatten function only works for an object whose keys are JSON Pointers and whose values are primitive. + +@since version 3.0.0 +*/ +class type_error : public exception +{ + public: + static type_error create(int id, const std::string& what_arg) + { + std::string w = exception::name("type_error", id) + what_arg; + return type_error(id, w.c_str()); + } -@invariant The member variables @a m_value and @a m_type have the following -relationship: -- If `m_type == value_t::object`, then `m_value.object != nullptr`. -- If `m_type == value_t::array`, then `m_value.array != nullptr`. -- If `m_type == value_t::string`, then `m_value.string != nullptr`. -The invariants are checked by member function assert_invariant(). + private: + type_error(int id_, const char* what_arg) + : exception(id_, what_arg) + {} +}; -@internal -@note ObjectType trick from http://stackoverflow.com/a/9860911 -@endinternal +/*! +@brief exception indicating access out of the defined range -@see [RFC 7159: The JavaScript Object Notation (JSON) Data Interchange -Format](http://rfc7159.net/rfc7159) +Exceptions have ids 4xx. -@since version 1.0.0 +name / id | example massage | description +------------------------------- | --------------- | ------------------------- +json.exception.out_of_range.401 | array index 3 is out of range | The provided array index @a i is larger than @a size-1. +json.exception.out_of_range.402 | array index '-' (3) is out of range | The special array index `-` in a JSON Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it. +json.exception.out_of_range.403 | key 'foo' not found | The provided key was not found in the JSON object. +json.exception.out_of_range.404 | unresolved reference token 'foo' | A reference token in a JSON Pointer could not be resolved. +json.exception.out_of_range.405 | JSON pointer has no parent | The JSON Patch operations 'remove' and 'add' can not be applied to the root element of the JSON value. +json.exception.out_of_range.406 | number overflow parsing '10E1000' | A parsed number could not be stored as without changing it to NaN or INF. -@nosubgrouping +@since version 3.0.0 */ -template < - template class ObjectType = std::map, - template class ArrayType = std::vector, - class StringType = std::string, - class BooleanType = bool, - class NumberIntegerType = std::int64_t, - class NumberUnsignedType = std::uint64_t, - class NumberFloatType = double, - template class AllocatorType = std::allocator - > -class basic_json +class out_of_range : public exception { + public: + static out_of_range create(int id, const std::string& what_arg) + { + std::string w = exception::name("out_of_range", id) + what_arg; + return out_of_range(id, w.c_str()); + } + private: - /// workaround type for MSVC - using basic_json_t = basic_json; + out_of_range(int id_, const char* what_arg) + : exception(id_, what_arg) + {} +}; - public: - // forward declarations - template class json_reverse_iterator; - class json_pointer; +/*! +@brief exception indicating other errors - ///////////////////// - // container types // - ///////////////////// +Exceptions have ids 5xx. - /// @name container types - /// The canonic container types to use @ref basic_json like any other STL - /// container. - /// @{ +name / id | example massage | description +------------------------------ | --------------- | ------------------------- +json.exception.other_error.501 | unsuccessful: {"op":"test","path":"/baz", "value":"bar"} | A JSON Patch operation 'test' failed. The unsuccessful operation is also printed. - /// the type of elements in a basic_json container - using value_type = basic_json; +@since version 3.0.0 +*/ +class other_error : public exception +{ + public: + static other_error create(int id, const std::string& what_arg) + { + std::string w = exception::name("other_error", id) + what_arg; + return other_error(id, w.c_str()); + } - /// the type of an element reference - using reference = value_type&; - /// the type of an element const reference - using const_reference = const value_type&; + private: + other_error(int id_, const char* what_arg) + : exception(id_, what_arg) + {} +}; - /// a type to represent differences between iterators - using difference_type = std::ptrdiff_t; - /// a type to represent container sizes - using size_type = std::size_t; - /// the allocator type - using allocator_type = AllocatorType; - /// the type of an element pointer - using pointer = typename std::allocator_traits::pointer; - /// the type of an element const pointer - using const_pointer = typename std::allocator_traits::const_pointer; +/////////////////////////// +// JSON type enumeration // +/////////////////////////// - /// an iterator for a basic_json container - class iterator; - /// a const iterator for a basic_json container - class const_iterator; - /// a reverse iterator for a basic_json container - using reverse_iterator = json_reverse_iterator; - /// a const reverse iterator for a basic_json container - using const_reverse_iterator = json_reverse_iterator; +/*! +@brief the JSON type enumeration + +This enumeration collects the different JSON types. It is internally used to +distinguish the stored values, and the functions @ref basic_json::is_null(), +@ref basic_json::is_object(), @ref basic_json::is_array(), +@ref basic_json::is_string(), @ref basic_json::is_boolean(), +@ref basic_json::is_number() (with @ref basic_json::is_number_integer(), +@ref basic_json::is_number_unsigned(), and @ref basic_json::is_number_float()), +@ref basic_json::is_discarded(), @ref basic_json::is_primitive(), and +@ref basic_json::is_structured() rely on it. + +@note There are three enumeration entries (number_integer, number_unsigned, and +number_float), because the library distinguishes these three types for numbers: +@ref basic_json::number_unsigned_t is used for unsigned integers, +@ref basic_json::number_integer_t is used for signed integers, and +@ref basic_json::number_float_t is used for floating-point numbers or to +approximate integers which do not fit in the limits of their respective type. + +@sa @ref basic_json::basic_json(const value_t value_type) -- create a JSON +value with the default value for a given type - /// @} +@since version 1.0.0 +*/ +enum class value_t : uint8_t +{ + null, ///< null value + object, ///< object (unordered set of name/value pairs) + array, ///< array (ordered collection of values) + string, ///< string value + boolean, ///< boolean value + number_integer, ///< number value (signed integer) + number_unsigned, ///< number value (unsigned integer) + number_float, ///< number value (floating-point) + discarded ///< discarded by the the parser callback function +}; + +/*! +@brief comparison operator for JSON types +Returns an ordering that is similar to Python: +- order: null < boolean < number < object < array < string +- furthermore, each type is not smaller than itself - /*! - @brief returns the allocator associated with the container - */ - static allocator_type get_allocator() +@since version 1.0.0 +*/ +inline bool operator<(const value_t lhs, const value_t rhs) noexcept +{ + static constexpr std::array order = {{ + 0, // null + 3, // object + 4, // array + 5, // string + 1, // boolean + 2, // integer + 2, // unsigned + 2, // float + } + }; + + // discarded values are not comparable + if (lhs == value_t::discarded or rhs == value_t::discarded) { - return allocator_type(); + return false; } + return order[static_cast(lhs)] < + order[static_cast(rhs)]; +} - /////////////////////////// - // JSON value data types // - /////////////////////////// - /// @name JSON value data types - /// The data types to store a JSON value. These types are derived from - /// the template arguments passed to class @ref basic_json. - /// @{ +///////////// +// helpers // +///////////// - /*! - @brief a type for an object +// alias templates to reduce boilerplate +template +using enable_if_t = typename std::enable_if::type; - [RFC 7159](http://rfc7159.net/rfc7159) describes JSON objects as follows: - > An object is an unordered collection of zero or more name/value pairs, - > where a name is a string and a value is a string, number, boolean, null, - > object, or array. +template +using uncvref_t = typename std::remove_cv::type>::type; - To store objects in C++, a type is defined by the template parameters - described below. +/* +Implementation of two C++17 constructs: conjunction, negation. This is needed +to avoid evaluating all the traits in a condition - @tparam ObjectType the container to store objects (e.g., `std::map` or - `std::unordered_map`) - @tparam StringType the type of the keys or names (e.g., `std::string`). - The comparison function `std::less` is used to order elements - inside the container. - @tparam AllocatorType the allocator to use for objects (e.g., - `std::allocator`) +For example: not std::is_same::value and has_value_type::value +will not compile when T = void (on MSVC at least). Whereas +conjunction>, has_value_type>::value will +stop evaluating if negation<...>::value == false - #### Default type +Please note that those constructs must be used with caution, since symbols can +become very long quickly (which can slow down compilation and cause MSVC +internal compiler errors). Only use it when you have to (see example ahead). +*/ +template struct conjunction : std::true_type {}; +template struct conjunction : B1 {}; +template +struct conjunction : std::conditional, B1>::type {}; - With the default values for @a ObjectType (`std::map`), @a StringType - (`std::string`), and @a AllocatorType (`std::allocator`), the default - value for @a object_t is: +template struct negation : std::integral_constant < bool, !B::value > {}; - @code {.cpp} - std::map< - std::string, // key_type - basic_json, // value_type - std::less, // key_compare - std::allocator> // allocator_type - > - @endcode +// dispatch utility (taken from ranges-v3) +template struct priority_tag : priority_tag < N - 1 > {}; +template<> struct priority_tag<0> {}; - #### Behavior - The choice of @a object_t influences the behavior of the JSON class. With - the default type, objects have the following behavior: +////////////////// +// constructors // +////////////////// - - When all names are unique, objects will be interoperable in the sense - that all software implementations receiving that object will agree on - the name-value mappings. - - When the names within an object are not unique, later stored name/value - pairs overwrite previously stored name/value pairs, leaving the used - names unique. For instance, `{"key": 1}` and `{"key": 2, "key": 1}` will - be treated as equal and both stored as `{"key": 1}`. - - Internally, name/value pairs are stored in lexicographical order of the - names. Objects will also be serialized (see @ref dump) in this order. - For instance, `{"b": 1, "a": 2}` and `{"a": 2, "b": 1}` will be stored - and serialized as `{"a": 2, "b": 1}`. - - When comparing objects, the order of the name/value pairs is irrelevant. - This makes objects interoperable in the sense that they will not be - affected by these differences. For instance, `{"b": 1, "a": 2}` and - `{"a": 2, "b": 1}` will be treated as equal. - - #### Limits - - [RFC 7159](http://rfc7159.net/rfc7159) specifies: - > An implementation may set limits on the maximum depth of nesting. - - In this class, the object's limit of nesting is not constraint explicitly. - However, a maximum depth of nesting may be introduced by the compiler or - runtime environment. A theoretical limit can be queried by calling the - @ref max_size function of a JSON object. +template struct external_constructor; - #### Storage +template<> +struct external_constructor +{ + template + static void construct(BasicJsonType& j, typename BasicJsonType::boolean_t b) noexcept + { + j.m_type = value_t::boolean; + j.m_value = b; + j.assert_invariant(); + } +}; - Objects are stored as pointers in a @ref basic_json type. That is, for any - access to object values, a pointer of type `object_t*` must be - dereferenced. +template<> +struct external_constructor +{ + template + static void construct(BasicJsonType& j, const typename BasicJsonType::string_t& s) + { + j.m_type = value_t::string; + j.m_value = s; + j.assert_invariant(); + } +}; - @sa @ref array_t -- type for an array value +template<> +struct external_constructor +{ + template + static void construct(BasicJsonType& j, typename BasicJsonType::number_float_t val) noexcept + { + j.m_type = value_t::number_float; + j.m_value = val; + j.assert_invariant(); + } +}; - @since version 1.0.0 +template<> +struct external_constructor +{ + template + static void construct(BasicJsonType& j, typename BasicJsonType::number_unsigned_t val) noexcept + { + j.m_type = value_t::number_unsigned; + j.m_value = val; + j.assert_invariant(); + } +}; - @note The order name/value pairs are added to the object is *not* - preserved by the library. Therefore, iterating an object may return - name/value pairs in a different order than they were originally stored. In - fact, keys will be traversed in alphabetical order as `std::map` with - `std::less` is used by default. Please note this behavior conforms to [RFC - 7159](http://rfc7159.net/rfc7159), because any order implements the - specified "unordered" nature of JSON objects. - */ - using object_t = ObjectType, - AllocatorType>>; +template<> +struct external_constructor +{ + template + static void construct(BasicJsonType& j, typename BasicJsonType::number_integer_t val) noexcept + { + j.m_type = value_t::number_integer; + j.m_value = val; + j.assert_invariant(); + } +}; - /*! - @brief a type for an array +template<> +struct external_constructor +{ + template + static void construct(BasicJsonType& j, const typename BasicJsonType::array_t& arr) + { + j.m_type = value_t::array; + j.m_value = arr; + j.assert_invariant(); + } - [RFC 7159](http://rfc7159.net/rfc7159) describes JSON arrays as follows: - > An array is an ordered sequence of zero or more values. + template::value, + int> = 0> + static void construct(BasicJsonType& j, const CompatibleArrayType& arr) + { + using std::begin; + using std::end; + j.m_type = value_t::array; + j.m_value.array = j.template create(begin(arr), end(arr)); + j.assert_invariant(); + } - To store objects in C++, a type is defined by the template parameters - explained below. + template + static void construct(BasicJsonType& j, const std::vector& arr) + { + j.m_type = value_t::array; + j.m_value = value_t::array; + j.m_value.array->reserve(arr.size()); + for (bool x : arr) + { + j.m_value.array->push_back(x); + } + j.assert_invariant(); + } +}; - @tparam ArrayType container type to store arrays (e.g., `std::vector` or - `std::list`) - @tparam AllocatorType allocator to use for arrays (e.g., `std::allocator`) +template<> +struct external_constructor +{ + template + static void construct(BasicJsonType& j, const typename BasicJsonType::object_t& obj) + { + j.m_type = value_t::object; + j.m_value = obj; + j.assert_invariant(); + } - #### Default type + template::value, + int> = 0> + static void construct(BasicJsonType& j, const CompatibleObjectType& obj) + { + using std::begin; + using std::end; - With the default values for @a ArrayType (`std::vector`) and @a - AllocatorType (`std::allocator`), the default value for @a array_t is: + j.m_type = value_t::object; + j.m_value.object = j.template create(begin(obj), end(obj)); + j.assert_invariant(); + } +}; - @code {.cpp} - std::vector< - basic_json, // value_type - std::allocator // allocator_type - > - @endcode - #### Limits +//////////////////////// +// has_/is_ functions // +//////////////////////// - [RFC 7159](http://rfc7159.net/rfc7159) specifies: - > An implementation may set limits on the maximum depth of nesting. +/*! +@brief Helper to determine whether there's a key_type for T. - In this class, the array's limit of nesting is not constraint explicitly. - However, a maximum depth of nesting may be introduced by the compiler or - runtime environment. A theoretical limit can be queried by calling the - @ref max_size function of a JSON array. +This helper is used to tell associative containers apart from other containers +such as sequence containers. For instance, `std::map` passes the test as it +contains a `mapped_type`, whereas `std::vector` fails the test. - #### Storage +@sa http://stackoverflow.com/a/7728728/266378 +@since version 1.0.0, overworked in version 2.0.6 +*/ +#define NLOHMANN_JSON_HAS_HELPER(type) \ + template struct has_##type { \ + private: \ + template \ + static int detect(U &&); \ + static void detect(...); \ + public: \ + static constexpr bool value = \ + std::is_integral()))>::value; \ + } - Arrays are stored as pointers in a @ref basic_json type. That is, for any - access to array values, a pointer of type `array_t*` must be dereferenced. +NLOHMANN_JSON_HAS_HELPER(mapped_type); +NLOHMANN_JSON_HAS_HELPER(key_type); +NLOHMANN_JSON_HAS_HELPER(value_type); +NLOHMANN_JSON_HAS_HELPER(iterator); - @sa @ref object_t -- type for an object value +#undef NLOHMANN_JSON_HAS_HELPER - @since version 1.0.0 - */ - using array_t = ArrayType>; - /*! - @brief a type for a string +template +struct is_compatible_object_type_impl : std::false_type {}; - [RFC 7159](http://rfc7159.net/rfc7159) describes JSON strings as follows: - > A string is a sequence of zero or more Unicode characters. +template +struct is_compatible_object_type_impl +{ + static constexpr auto value = + std::is_constructible::value and + std::is_constructible::value; +}; - To store objects in C++, a type is defined by the template parameter - described below. Unicode values are split by the JSON class into - byte-sized characters during deserialization. +template +struct is_compatible_object_type +{ + static auto constexpr value = is_compatible_object_type_impl < + conjunction>, + has_mapped_type, + has_key_type>::value, + typename BasicJsonType::object_t, CompatibleObjectType >::value; +}; - @tparam StringType the container to store strings (e.g., `std::string`). - Note this container is used for keys/names in objects, see @ref object_t. +template +struct is_basic_json_nested_type +{ + static auto constexpr value = std::is_same::value or + std::is_same::value or + std::is_same::value or + std::is_same::value or + std::is_same::value; +}; - #### Default type +template +struct is_compatible_array_type +{ + static auto constexpr value = + conjunction>, + negation>, + negation>, + negation>, + has_value_type, + has_iterator>::value; +}; - With the default values for @a StringType (`std::string`), the default - value for @a string_t is: +template +struct is_compatible_integer_type_impl : std::false_type {}; - @code {.cpp} - std::string - @endcode +template +struct is_compatible_integer_type_impl +{ + // is there an assert somewhere on overflows? + using RealLimits = std::numeric_limits; + using CompatibleLimits = std::numeric_limits; + + static constexpr auto value = + std::is_constructible::value and + CompatibleLimits::is_integer and + RealLimits::is_signed == CompatibleLimits::is_signed; +}; - #### String comparison +template +struct is_compatible_integer_type +{ + static constexpr auto value = + is_compatible_integer_type_impl < + std::is_integral::value and + not std::is_same::value, + RealIntegerType, CompatibleNumberIntegerType > ::value; +}; - [RFC 7159](http://rfc7159.net/rfc7159) states: - > Software implementations are typically required to test names of object - > members for equality. Implementations that transform the textual - > representation into sequences of Unicode code units and then perform the - > comparison numerically, code unit by code unit, are interoperable in the - > sense that implementations will agree in all cases on equality or - > inequality of two strings. For example, implementations that compare - > strings with escaped characters unconverted may incorrectly find that - > `"a\\b"` and `"a\u005Cb"` are not equal. - This implementation is interoperable as it does compare strings code unit - by code unit. +// trait checking if JSONSerializer::from_json(json const&, udt&) exists +template +struct has_from_json +{ + private: + // also check the return type of from_json + template::from_json( + std::declval(), std::declval()))>::value>> + static int detect(U&&); + static void detect(...); - #### Storage + public: + static constexpr bool value = std::is_integral>()))>::value; +}; - String values are stored as pointers in a @ref basic_json type. That is, - for any access to string values, a pointer of type `string_t*` must be - dereferenced. +// This trait checks if JSONSerializer::from_json(json const&) exists +// this overload is used for non-default-constructible user-defined-types +template +struct has_non_default_from_json +{ + private: + template < + typename U, + typename = enable_if_t::from_json(std::declval()))>::value >> + static int detect(U&&); + static void detect(...); - @since version 1.0.0 - */ - using string_t = StringType; + public: + static constexpr bool value = std::is_integral>()))>::value; +}; - /*! - @brief a type for a boolean +// This trait checks if BasicJsonType::json_serializer::to_json exists +template +struct has_to_json +{ + private: + template::to_json( + std::declval(), std::declval()))> + static int detect(U&&); + static void detect(...); - [RFC 7159](http://rfc7159.net/rfc7159) implicitly describes a boolean as a - type which differentiates the two literals `true` and `false`. + public: + static constexpr bool value = std::is_integral>()))>::value; +}; - To store objects in C++, a type is defined by the template parameter @a - BooleanType which chooses the type to use. - #### Default type +///////////// +// to_json // +///////////// - With the default values for @a BooleanType (`bool`), the default value for - @a boolean_t is: +template::value, int> = 0> +void to_json(BasicJsonType& j, T b) noexcept +{ + external_constructor::construct(j, b); +} - @code {.cpp} - bool - @endcode +template::value, int> = 0> +void to_json(BasicJsonType& j, const CompatibleString& s) +{ + external_constructor::construct(j, s); +} - #### Storage +template::value, int> = 0> +void to_json(BasicJsonType& j, FloatType val) noexcept +{ + external_constructor::construct(j, static_cast(val)); +} - Boolean values are stored directly inside a @ref basic_json type. +template < + typename BasicJsonType, typename CompatibleNumberUnsignedType, + enable_if_t::value, int> = 0 > +void to_json(BasicJsonType& j, CompatibleNumberUnsignedType val) noexcept +{ + external_constructor::construct(j, static_cast(val)); +} - @since version 1.0.0 - */ - using boolean_t = BooleanType; +template < + typename BasicJsonType, typename CompatibleNumberIntegerType, + enable_if_t::value, int> = 0 > +void to_json(BasicJsonType& j, CompatibleNumberIntegerType val) noexcept +{ + external_constructor::construct(j, static_cast(val)); +} - /*! - @brief a type for a number (integer) +template::value, int> = 0> +void to_json(BasicJsonType& j, EnumType e) noexcept +{ + using underlying_type = typename std::underlying_type::type; + external_constructor::construct(j, static_cast(e)); +} - [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows: - > The representation of numbers is similar to that used in most - > programming languages. A number is represented in base 10 using decimal - > digits. It contains an integer component that may be prefixed with an - > optional minus sign, which may be followed by a fraction part and/or an - > exponent part. Leading zeros are not allowed. (...) Numeric values that - > cannot be represented in the grammar below (such as Infinity and NaN) - > are not permitted. +template +void to_json(BasicJsonType& j, const std::vector& e) +{ + external_constructor::construct(j, e); +} - This description includes both integer and floating-point numbers. - However, C++ allows more precise storage if it is known whether the number - is a signed integer, an unsigned integer or a floating-point number. - Therefore, three different types, @ref number_integer_t, @ref - number_unsigned_t and @ref number_float_t are used. +template < + typename BasicJsonType, typename CompatibleArrayType, + enable_if_t < + is_compatible_array_type::value or + std::is_same::value, + int > = 0 > +void to_json(BasicJsonType& j, const CompatibleArrayType& arr) +{ + external_constructor::construct(j, arr); +} - To store integer numbers in C++, a type is defined by the template - parameter @a NumberIntegerType which chooses the type to use. +template < + typename BasicJsonType, typename CompatibleObjectType, + enable_if_t::value, + int> = 0 > +void to_json(BasicJsonType& j, const CompatibleObjectType& arr) +{ + external_constructor::construct(j, arr); +} - #### Default type +template ::value, + int> = 0> +void to_json(BasicJsonType& j, T (&arr)[N]) +{ + external_constructor::construct(j, arr); +} - With the default values for @a NumberIntegerType (`int64_t`), the default - value for @a number_integer_t is: - - @code {.cpp} - int64_t - @endcode +/////////////// +// from_json // +/////////////// + +// overloads for basic_json template parameters +template::value and + not std::is_same::value, + int> = 0> +void get_arithmetic_value(const BasicJsonType& j, ArithmeticType& val) +{ + switch (static_cast(j)) + { + case value_t::number_unsigned: + { + val = static_cast( + *j.template get_ptr()); + break; + } + case value_t::number_integer: + { + val = static_cast( + *j.template get_ptr()); + break; + } + case value_t::number_float: + { + val = static_cast( + *j.template get_ptr()); + break; + } + default: + { + JSON_THROW(type_error::create(302, "type must be number, but is " + j.type_name())); + } + } +} - #### Default behavior +template +void from_json(const BasicJsonType& j, typename BasicJsonType::boolean_t& b) +{ + if (not j.is_boolean()) + { + JSON_THROW(type_error::create(302, "type must be boolean, but is " + j.type_name())); + } + b = *j.template get_ptr(); +} - - The restrictions about leading zeros is not enforced in C++. Instead, - leading zeros in integer literals lead to an interpretation as octal - number. Internally, the value will be stored as decimal number. For - instance, the C++ integer literal `010` will be serialized to `8`. - During deserialization, leading zeros yield an error. - - Not-a-number (NaN) values will be serialized to `null`. +template +void from_json(const BasicJsonType& j, typename BasicJsonType::string_t& s) +{ + if (not j.is_string()) + { + JSON_THROW(type_error::create(302, "type must be string, but is " + j.type_name())); + } + s = *j.template get_ptr(); +} - #### Limits +template +void from_json(const BasicJsonType& j, typename BasicJsonType::number_float_t& val) +{ + get_arithmetic_value(j, val); +} - [RFC 7159](http://rfc7159.net/rfc7159) specifies: - > An implementation may set limits on the range and precision of numbers. +template +void from_json(const BasicJsonType& j, typename BasicJsonType::number_unsigned_t& val) +{ + get_arithmetic_value(j, val); +} - When the default type is used, the maximal integer number that can be - stored is `9223372036854775807` (INT64_MAX) and the minimal integer number - that can be stored is `-9223372036854775808` (INT64_MIN). Integer numbers - that are out of range will yield over/underflow when used in a - constructor. During deserialization, too large or small integer numbers - will be automatically be stored as @ref number_unsigned_t or @ref - number_float_t. +template +void from_json(const BasicJsonType& j, typename BasicJsonType::number_integer_t& val) +{ + get_arithmetic_value(j, val); +} - [RFC 7159](http://rfc7159.net/rfc7159) further states: - > Note that when such software is used, numbers that are integers and are - > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense - > that implementations will agree exactly on their numeric values. +template::value, int> = 0> +void from_json(const BasicJsonType& j, EnumType& e) +{ + typename std::underlying_type::type val; + get_arithmetic_value(j, val); + e = static_cast(val); +} - As this range is a subrange of the exactly supported range [INT64_MIN, - INT64_MAX], this class's integer type is interoperable. +template +void from_json(const BasicJsonType& j, typename BasicJsonType::array_t& arr) +{ + if (not j.is_array()) + { + JSON_THROW(type_error::create(302, "type must be array, but is " + j.type_name())); + } + arr = *j.template get_ptr(); +} - #### Storage +// forward_list doesn't have an insert method +template::value, int> = 0> +void from_json(const BasicJsonType& j, std::forward_list& l) +{ + if (not j.is_array()) + { + JSON_THROW(type_error::create(302, "type must be array, but is " + j.type_name())); + } - Integer number values are stored directly inside a @ref basic_json type. + for (auto it = j.rbegin(), end = j.rend(); it != end; ++it) + { + l.push_front(it->template get()); + } +} - @sa @ref number_float_t -- type for number values (floating-point) +template +void from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, priority_tag<0>) +{ + using std::begin; + using std::end; - @sa @ref number_unsigned_t -- type for number values (unsigned integer) + std::transform(j.begin(), j.end(), + std::inserter(arr, end(arr)), [](const BasicJsonType & i) + { + // get() returns *this, this won't call a from_json + // method when value_type is BasicJsonType + return i.template get(); + }); +} - @since version 1.0.0 - */ - using number_integer_t = NumberIntegerType; +template +auto from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, priority_tag<1>) +-> decltype( + arr.reserve(std::declval()), + void()) +{ + using std::begin; + using std::end; - /*! - @brief a type for a number (unsigned) + arr.reserve(j.size()); + std::transform(j.begin(), j.end(), + std::inserter(arr, end(arr)), [](const BasicJsonType & i) + { + // get() returns *this, this won't call a from_json + // method when value_type is BasicJsonType + return i.template get(); + }); +} - [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows: - > The representation of numbers is similar to that used in most - > programming languages. A number is represented in base 10 using decimal - > digits. It contains an integer component that may be prefixed with an - > optional minus sign, which may be followed by a fraction part and/or an - > exponent part. Leading zeros are not allowed. (...) Numeric values that - > cannot be represented in the grammar below (such as Infinity and NaN) - > are not permitted. +template::value and + std::is_convertible::value and + not std::is_same::value, int> = 0> +void from_json(const BasicJsonType& j, CompatibleArrayType& arr) +{ + if (not j.is_array()) + { + JSON_THROW(type_error::create(302, "type must be array, but is " + j.type_name())); + } - This description includes both integer and floating-point numbers. - However, C++ allows more precise storage if it is known whether the number - is a signed integer, an unsigned integer or a floating-point number. - Therefore, three different types, @ref number_integer_t, @ref - number_unsigned_t and @ref number_float_t are used. + from_json_array_impl(j, arr, priority_tag<1> {}); +} - To store unsigned integer numbers in C++, a type is defined by the - template parameter @a NumberUnsignedType which chooses the type to use. +template::value, int> = 0> +void from_json(const BasicJsonType& j, CompatibleObjectType& obj) +{ + if (not j.is_object()) + { + JSON_THROW(type_error::create(302, "type must be object, but is " + j.type_name())); + } - #### Default type + auto inner_object = j.template get_ptr(); + using std::begin; + using std::end; + // we could avoid the assignment, but this might require a for loop, which + // might be less efficient than the container constructor for some + // containers (would it?) + obj = CompatibleObjectType(begin(*inner_object), end(*inner_object)); +} - With the default values for @a NumberUnsignedType (`uint64_t`), the - default value for @a number_unsigned_t is: +// overload for arithmetic types, not chosen for basic_json template arguments +// (BooleanType, etc..); note: Is it really necessary to provide explicit +// overloads for boolean_t etc. in case of a custom BooleanType which is not +// an arithmetic type? +template::value and + not std::is_same::value and + not std::is_same::value and + not std::is_same::value and + not std::is_same::value, + int> = 0> +void from_json(const BasicJsonType& j, ArithmeticType& val) +{ + switch (static_cast(j)) + { + case value_t::number_unsigned: + { + val = static_cast(*j.template get_ptr()); + break; + } + case value_t::number_integer: + { + val = static_cast(*j.template get_ptr()); + break; + } + case value_t::number_float: + { + val = static_cast(*j.template get_ptr()); + break; + } + case value_t::boolean: + { + val = static_cast(*j.template get_ptr()); + break; + } + default: + { + JSON_THROW(type_error::create(302, "type must be number, but is " + j.type_name())); + } + } +} - @code {.cpp} - uint64_t - @endcode +struct to_json_fn +{ + private: + template + auto call(BasicJsonType& j, T&& val, priority_tag<1>) const noexcept(noexcept(to_json(j, std::forward(val)))) + -> decltype(to_json(j, std::forward(val)), void()) + { + return to_json(j, std::forward(val)); + } - #### Default behavior + template + void call(BasicJsonType&, T&&, priority_tag<0>) const noexcept + { + static_assert(sizeof(BasicJsonType) == 0, + "could not find to_json() method in T's namespace"); + } - - The restrictions about leading zeros is not enforced in C++. Instead, - leading zeros in integer literals lead to an interpretation as octal - number. Internally, the value will be stored as decimal number. For - instance, the C++ integer literal `010` will be serialized to `8`. - During deserialization, leading zeros yield an error. - - Not-a-number (NaN) values will be serialized to `null`. + public: + template + void operator()(BasicJsonType& j, T&& val) const + noexcept(noexcept(std::declval().call(j, std::forward(val), priority_tag<1> {}))) + { + return call(j, std::forward(val), priority_tag<1> {}); + } +}; - #### Limits +struct from_json_fn +{ + private: + template + auto call(const BasicJsonType& j, T& val, priority_tag<1>) const + noexcept(noexcept(from_json(j, val))) + -> decltype(from_json(j, val), void()) + { + return from_json(j, val); + } - [RFC 7159](http://rfc7159.net/rfc7159) specifies: - > An implementation may set limits on the range and precision of numbers. + template + void call(const BasicJsonType&, T&, priority_tag<0>) const noexcept + { + static_assert(sizeof(BasicJsonType) == 0, + "could not find from_json() method in T's namespace"); + } - When the default type is used, the maximal integer number that can be - stored is `18446744073709551615` (UINT64_MAX) and the minimal integer - number that can be stored is `0`. Integer numbers that are out of range - will yield over/underflow when used in a constructor. During - deserialization, too large or small integer numbers will be automatically - be stored as @ref number_integer_t or @ref number_float_t. + public: + template + void operator()(const BasicJsonType& j, T& val) const + noexcept(noexcept(std::declval().call(j, val, priority_tag<1> {}))) + { + return call(j, val, priority_tag<1> {}); + } +}; - [RFC 7159](http://rfc7159.net/rfc7159) further states: - > Note that when such software is used, numbers that are integers and are - > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense - > that implementations will agree exactly on their numeric values. +// taken from ranges-v3 +template +struct static_const +{ + static constexpr T value{}; +}; - As this range is a subrange (when considered in conjunction with the - number_integer_t type) of the exactly supported range [0, UINT64_MAX], - this class's integer type is interoperable. +template +constexpr T static_const::value; +} // namespace detail - #### Storage - Integer number values are stored directly inside a @ref basic_json type. +/// namespace to hold default `to_json` / `from_json` functions +namespace +{ +constexpr const auto& to_json = detail::static_const::value; +constexpr const auto& from_json = detail::static_const::value; +} - @sa @ref number_float_t -- type for number values (floating-point) - @sa @ref number_integer_t -- type for number values (integer) - @since version 2.0.0 - */ - using number_unsigned_t = NumberUnsignedType; +/*! +@brief default JSONSerializer template argument +This serializer ignores the template arguments and uses ADL +([argument-dependent lookup](http://en.cppreference.com/w/cpp/language/adl)) +for serialization. +*/ +template +struct adl_serializer +{ /*! - @brief a type for a number (floating-point) - - [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows: - > The representation of numbers is similar to that used in most - > programming languages. A number is represented in base 10 using decimal - > digits. It contains an integer component that may be prefixed with an - > optional minus sign, which may be followed by a fraction part and/or an - > exponent part. Leading zeros are not allowed. (...) Numeric values that - > cannot be represented in the grammar below (such as Infinity and NaN) - > are not permitted. - - This description includes both integer and floating-point numbers. - However, C++ allows more precise storage if it is known whether the number - is a signed integer, an unsigned integer or a floating-point number. - Therefore, three different types, @ref number_integer_t, @ref - number_unsigned_t and @ref number_float_t are used. - - To store floating-point numbers in C++, a type is defined by the template - parameter @a NumberFloatType which chooses the type to use. - - #### Default type - - With the default values for @a NumberFloatType (`double`), the default - value for @a number_float_t is: - - @code {.cpp} - double - @endcode - - #### Default behavior - - - The restrictions about leading zeros is not enforced in C++. Instead, - leading zeros in floating-point literals will be ignored. Internally, - the value will be stored as decimal number. For instance, the C++ - floating-point literal `01.2` will be serialized to `1.2`. During - deserialization, leading zeros yield an error. - - Not-a-number (NaN) values will be serialized to `null`. - - #### Limits + @brief convert a JSON value to any value type - [RFC 7159](http://rfc7159.net/rfc7159) states: - > This specification allows implementations to set limits on the range and - > precision of numbers accepted. Since software that implements IEEE - > 754-2008 binary64 (double precision) numbers is generally available and - > widely used, good interoperability can be achieved by implementations - > that expect no more precision or range than these provide, in the sense - > that implementations will approximate JSON numbers within the expected - > precision. + This function is usually called by the `get()` function of the + @ref basic_json class (either explicit or via conversion operators). - This implementation does exactly follow this approach, as it uses double - precision floating-point numbers. Note values smaller than - `-1.79769313486232e+308` and values greater than `1.79769313486232e+308` - will be stored as NaN internally and be serialized to `null`. - - #### Storage - - Floating-point number values are stored directly inside a @ref basic_json - type. + @param[in] j JSON value to read from + @param[in,out] val value to write to + */ + template + static void from_json(BasicJsonType&& j, ValueType& val) noexcept( + noexcept(::nlohmann::from_json(std::forward(j), val))) + { + ::nlohmann::from_json(std::forward(j), val); + } - @sa @ref number_integer_t -- type for number values (integer) + /*! + @brief convert any value type to a JSON value - @sa @ref number_unsigned_t -- type for number values (unsigned integer) + This function is usually called by the constructors of the @ref basic_json + class. - @since version 1.0.0 + @param[in,out] j JSON value to write to + @param[in] val value to read from */ - using number_float_t = NumberFloatType; + template + static void to_json(BasicJsonType& j, ValueType&& val) noexcept( + noexcept(::nlohmann::to_json(j, std::forward(val)))) + { + ::nlohmann::to_json(j, std::forward(val)); + } +}; - /// @} + +/*! +@brief a class to store JSON values + +@tparam ObjectType type for JSON objects (`std::map` by default; will be used +in @ref object_t) +@tparam ArrayType type for JSON arrays (`std::vector` by default; will be used +in @ref array_t) +@tparam StringType type for JSON strings and object keys (`std::string` by +default; will be used in @ref string_t) +@tparam BooleanType type for JSON booleans (`bool` by default; will be used +in @ref boolean_t) +@tparam NumberIntegerType type for JSON integer numbers (`int64_t` by +default; will be used in @ref number_integer_t) +@tparam NumberUnsignedType type for JSON unsigned integer numbers (@c +`uint64_t` by default; will be used in @ref number_unsigned_t) +@tparam NumberFloatType type for JSON floating-point numbers (`double` by +default; will be used in @ref number_float_t) +@tparam AllocatorType type of the allocator to use (`std::allocator` by +default) +@tparam JSONSerializer the serializer to resolve internal calls to `to_json()` +and `from_json()` (@ref adl_serializer by default) + +@requirement The class satisfies the following concept requirements: +- Basic + - [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible): + JSON values can be default constructed. The result will be a JSON null + value. + - [MoveConstructible](http://en.cppreference.com/w/cpp/concept/MoveConstructible): + A JSON value can be constructed from an rvalue argument. + - [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible): + A JSON value can be copy-constructed from an lvalue expression. + - [MoveAssignable](http://en.cppreference.com/w/cpp/concept/MoveAssignable): + A JSON value van be assigned from an rvalue argument. + - [CopyAssignable](http://en.cppreference.com/w/cpp/concept/CopyAssignable): + A JSON value can be copy-assigned from an lvalue expression. + - [Destructible](http://en.cppreference.com/w/cpp/concept/Destructible): + JSON values can be destructed. +- Layout + - [StandardLayoutType](http://en.cppreference.com/w/cpp/concept/StandardLayoutType): + JSON values have + [standard layout](http://en.cppreference.com/w/cpp/language/data_members#Standard_layout): + All non-static data members are private and standard layout types, the + class has no virtual functions or (virtual) base classes. +- Library-wide + - [EqualityComparable](http://en.cppreference.com/w/cpp/concept/EqualityComparable): + JSON values can be compared with `==`, see @ref + operator==(const_reference,const_reference). + - [LessThanComparable](http://en.cppreference.com/w/cpp/concept/LessThanComparable): + JSON values can be compared with `<`, see @ref + operator<(const_reference,const_reference). + - [Swappable](http://en.cppreference.com/w/cpp/concept/Swappable): + Any JSON lvalue or rvalue of can be swapped with any lvalue or rvalue of + other compatible types, using unqualified function call @ref swap(). + - [NullablePointer](http://en.cppreference.com/w/cpp/concept/NullablePointer): + JSON values can be compared against `std::nullptr_t` objects which are used + to model the `null` value. +- Container + - [Container](http://en.cppreference.com/w/cpp/concept/Container): + JSON values can be used like STL containers and provide iterator access. + - [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer); + JSON values can be used like STL containers and provide reverse iterator + access. + +@invariant The member variables @a m_value and @a m_type have the following +relationship: +- If `m_type == value_t::object`, then `m_value.object != nullptr`. +- If `m_type == value_t::array`, then `m_value.array != nullptr`. +- If `m_type == value_t::string`, then `m_value.string != nullptr`. +The invariants are checked by member function assert_invariant(). + +@internal +@note ObjectType trick from http://stackoverflow.com/a/9860911 +@endinternal + +@see [RFC 7159: The JavaScript Object Notation (JSON) Data Interchange +Format](http://rfc7159.net/rfc7159) + +@since version 1.0.0 + +@nosubgrouping +*/ +template < + template class ObjectType = std::map, + template class ArrayType = std::vector, + class StringType = std::string, + class BooleanType = bool, + class NumberIntegerType = std::int64_t, + class NumberUnsignedType = std::uint64_t, + class NumberFloatType = double, + template class AllocatorType = std::allocator, + template class JSONSerializer = adl_serializer + > +class basic_json +{ + private: + template friend struct detail::external_constructor; + /// workaround type for MSVC + using basic_json_t = basic_json; + + public: + using value_t = detail::value_t; + // forward declarations + template class iter_impl; + template class json_reverse_iterator; + class json_pointer; + template + using json_serializer = JSONSerializer; + + + //////////////// + // exceptions // + //////////////// + + /// @name exceptions + /// Classes to implement user-defined exceptions. + /// @{ + + /// @copydoc detail::exception + using exception = detail::exception; + /// @copydoc detail::parse_error + using parse_error = detail::parse_error; + /// @copydoc detail::invalid_iterator + using invalid_iterator = detail::invalid_iterator; + /// @copydoc detail::type_error + using type_error = detail::type_error; + /// @copydoc detail::out_of_range + using out_of_range = detail::out_of_range; + /// @copydoc detail::other_error + using other_error = detail::other_error; + + /// @} + + + ///////////////////// + // container types // + ///////////////////// + + /// @name container types + /// The canonic container types to use @ref basic_json like any other STL + /// container. + /// @{ + + /// the type of elements in a basic_json container + using value_type = basic_json; + + /// the type of an element reference + using reference = value_type&; + /// the type of an element const reference + using const_reference = const value_type&; + + /// a type to represent differences between iterators + using difference_type = std::ptrdiff_t; + /// a type to represent container sizes + using size_type = std::size_t; + + /// the allocator type + using allocator_type = AllocatorType; + + /// the type of an element pointer + using pointer = typename std::allocator_traits::pointer; + /// the type of an element const pointer + using const_pointer = typename std::allocator_traits::const_pointer; + + /// an iterator for a basic_json container + using iterator = iter_impl; + /// a const iterator for a basic_json container + using const_iterator = iter_impl; + /// a reverse iterator for a basic_json container + using reverse_iterator = json_reverse_iterator; + /// a const reverse iterator for a basic_json container + using const_reverse_iterator = json_reverse_iterator; + + /// @} + + + /*! + @brief returns the allocator associated with the container + */ + static allocator_type get_allocator() + { + return allocator_type(); + } + + /*! + @brief returns version information on the library + + This function returns a JSON object with information about the library, + including the version number and information on the platform and compiler. + + @return JSON object holding version information + key | description + ----------- | --------------- + `compiler` | Information on the used compiler. It is an object with the following keys: `c++` (the used C++ standard), `family` (the compiler family; possible values are `clang`, `icc`, `gcc`, `ilecpp`, `msvc`, `pgcpp`, `sunpro`, and `unknown`), and `version` (the compiler version). + `copyright` | The copyright line for the library as string. + `name` | The name of the library as string. + `platform` | The used platform as string. Possible values are `win32`, `linux`, `apple`, `unix`, and `unknown`. + `url` | The URL of the project as string. + `version` | The version of the library. It is an object with the following keys: `major`, `minor`, and `patch` as defined by [Semantic Versioning](http://semver.org), and `string` (the version string). + + @liveexample{The following code shows an example output of the `meta()` + function.,meta} + + @complexity Constant. + + @since 2.1.0 + */ + static basic_json meta() + { + basic_json result; + + result["copyright"] = "(C) 2013-2017 Niels Lohmann"; + result["name"] = "JSON for Modern C++"; + result["url"] = "https://github.com/nlohmann/json"; + result["version"] = + { + {"string", "2.1.1"}, {"major", 2}, {"minor", 1}, {"patch", 1} + }; + +#ifdef _WIN32 + result["platform"] = "win32"; +#elif defined __linux__ + result["platform"] = "linux"; +#elif defined __APPLE__ + result["platform"] = "apple"; +#elif defined __unix__ + result["platform"] = "unix"; +#else + result["platform"] = "unknown"; +#endif + +#if defined(__clang__) + result["compiler"] = {{"family", "clang"}, {"version", __clang_version__}}; +#elif defined(__ICC) || defined(__INTEL_COMPILER) + result["compiler"] = {{"family", "icc"}, {"version", __INTEL_COMPILER}}; +#elif defined(__GNUC__) || defined(__GNUG__) + result["compiler"] = {{"family", "gcc"}, {"version", std::to_string(__GNUC__) + "." + std::to_string(__GNUC_MINOR__) + "." + std::to_string(__GNUC_PATCHLEVEL__)}}; +#elif defined(__HP_cc) || defined(__HP_aCC) + result["compiler"] = "hp" +#elif defined(__IBMCPP__) + result["compiler"] = {{"family", "ilecpp"}, {"version", __IBMCPP__}}; +#elif defined(_MSC_VER) + result["compiler"] = {{"family", "msvc"}, {"version", _MSC_VER}}; +#elif defined(__PGI) + result["compiler"] = {{"family", "pgcpp"}, {"version", __PGI}}; +#elif defined(__SUNPRO_CC) + result["compiler"] = {{"family", "sunpro"}, {"version", __SUNPRO_CC}}; +#else + result["compiler"] = {{"family", "unknown"}, {"version", "unknown"}}; +#endif + +#ifdef __cplusplus + result["compiler"]["c++"] = std::to_string(__cplusplus); +#else + result["compiler"]["c++"] = "unknown"; +#endif + return result; + } /////////////////////////// - // JSON type enumeration // - /////////////////////////// + // JSON value data types // + /////////////////////////// + + /// @name JSON value data types + /// The data types to store a JSON value. These types are derived from + /// the template arguments passed to class @ref basic_json. + /// @{ + + /*! + @brief a type for an object + + [RFC 7159](http://rfc7159.net/rfc7159) describes JSON objects as follows: + > An object is an unordered collection of zero or more name/value pairs, + > where a name is a string and a value is a string, number, boolean, null, + > object, or array. + + To store objects in C++, a type is defined by the template parameters + described below. + + @tparam ObjectType the container to store objects (e.g., `std::map` or + `std::unordered_map`) + @tparam StringType the type of the keys or names (e.g., `std::string`). + The comparison function `std::less` is used to order elements + inside the container. + @tparam AllocatorType the allocator to use for objects (e.g., + `std::allocator`) + + #### Default type + + With the default values for @a ObjectType (`std::map`), @a StringType + (`std::string`), and @a AllocatorType (`std::allocator`), the default + value for @a object_t is: + + @code {.cpp} + std::map< + std::string, // key_type + basic_json, // value_type + std::less, // key_compare + std::allocator> // allocator_type + > + @endcode + + #### Behavior + + The choice of @a object_t influences the behavior of the JSON class. With + the default type, objects have the following behavior: + + - When all names are unique, objects will be interoperable in the sense + that all software implementations receiving that object will agree on + the name-value mappings. + - When the names within an object are not unique, later stored name/value + pairs overwrite previously stored name/value pairs, leaving the used + names unique. For instance, `{"key": 1}` and `{"key": 2, "key": 1}` will + be treated as equal and both stored as `{"key": 1}`. + - Internally, name/value pairs are stored in lexicographical order of the + names. Objects will also be serialized (see @ref dump) in this order. + For instance, `{"b": 1, "a": 2}` and `{"a": 2, "b": 1}` will be stored + and serialized as `{"a": 2, "b": 1}`. + - When comparing objects, the order of the name/value pairs is irrelevant. + This makes objects interoperable in the sense that they will not be + affected by these differences. For instance, `{"b": 1, "a": 2}` and + `{"a": 2, "b": 1}` will be treated as equal. + + #### Limits + + [RFC 7159](http://rfc7159.net/rfc7159) specifies: + > An implementation may set limits on the maximum depth of nesting. + + In this class, the object's limit of nesting is not constraint explicitly. + However, a maximum depth of nesting may be introduced by the compiler or + runtime environment. A theoretical limit can be queried by calling the + @ref max_size function of a JSON object. + + #### Storage + + Objects are stored as pointers in a @ref basic_json type. That is, for any + access to object values, a pointer of type `object_t*` must be + dereferenced. + + @sa @ref array_t -- type for an array value + + @since version 1.0.0 + + @note The order name/value pairs are added to the object is *not* + preserved by the library. Therefore, iterating an object may return + name/value pairs in a different order than they were originally stored. In + fact, keys will be traversed in alphabetical order as `std::map` with + `std::less` is used by default. Please note this behavior conforms to [RFC + 7159](http://rfc7159.net/rfc7159), because any order implements the + specified "unordered" nature of JSON objects. + */ + using object_t = ObjectType, + AllocatorType>>; + + /*! + @brief a type for an array + + [RFC 7159](http://rfc7159.net/rfc7159) describes JSON arrays as follows: + > An array is an ordered sequence of zero or more values. + + To store objects in C++, a type is defined by the template parameters + explained below. + + @tparam ArrayType container type to store arrays (e.g., `std::vector` or + `std::list`) + @tparam AllocatorType allocator to use for arrays (e.g., `std::allocator`) + + #### Default type + + With the default values for @a ArrayType (`std::vector`) and @a + AllocatorType (`std::allocator`), the default value for @a array_t is: + + @code {.cpp} + std::vector< + basic_json, // value_type + std::allocator // allocator_type + > + @endcode + + #### Limits + + [RFC 7159](http://rfc7159.net/rfc7159) specifies: + > An implementation may set limits on the maximum depth of nesting. + + In this class, the array's limit of nesting is not constraint explicitly. + However, a maximum depth of nesting may be introduced by the compiler or + runtime environment. A theoretical limit can be queried by calling the + @ref max_size function of a JSON array. + + #### Storage + + Arrays are stored as pointers in a @ref basic_json type. That is, for any + access to array values, a pointer of type `array_t*` must be dereferenced. + + @sa @ref object_t -- type for an object value + + @since version 1.0.0 + */ + using array_t = ArrayType>; + + /*! + @brief a type for a string + + [RFC 7159](http://rfc7159.net/rfc7159) describes JSON strings as follows: + > A string is a sequence of zero or more Unicode characters. + + To store objects in C++, a type is defined by the template parameter + described below. Unicode values are split by the JSON class into + byte-sized characters during deserialization. + + @tparam StringType the container to store strings (e.g., `std::string`). + Note this container is used for keys/names in objects, see @ref object_t. + + #### Default type + + With the default values for @a StringType (`std::string`), the default + value for @a string_t is: + + @code {.cpp} + std::string + @endcode + + #### Encoding + + Strings are stored in UTF-8 encoding. Therefore, functions like + `std::string::size()` or `std::string::length()` return the number of + bytes in the string rather than the number of characters or glyphs. + + #### String comparison + + [RFC 7159](http://rfc7159.net/rfc7159) states: + > Software implementations are typically required to test names of object + > members for equality. Implementations that transform the textual + > representation into sequences of Unicode code units and then perform the + > comparison numerically, code unit by code unit, are interoperable in the + > sense that implementations will agree in all cases on equality or + > inequality of two strings. For example, implementations that compare + > strings with escaped characters unconverted may incorrectly find that + > `"a\\b"` and `"a\u005Cb"` are not equal. + + This implementation is interoperable as it does compare strings code unit + by code unit. + + #### Storage + + String values are stored as pointers in a @ref basic_json type. That is, + for any access to string values, a pointer of type `string_t*` must be + dereferenced. + + @since version 1.0.0 + */ + using string_t = StringType; + + /*! + @brief a type for a boolean + + [RFC 7159](http://rfc7159.net/rfc7159) implicitly describes a boolean as a + type which differentiates the two literals `true` and `false`. + + To store objects in C++, a type is defined by the template parameter @a + BooleanType which chooses the type to use. + + #### Default type + + With the default values for @a BooleanType (`bool`), the default value for + @a boolean_t is: + + @code {.cpp} + bool + @endcode + + #### Storage + + Boolean values are stored directly inside a @ref basic_json type. + + @since version 1.0.0 + */ + using boolean_t = BooleanType; + + /*! + @brief a type for a number (integer) + + [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows: + > The representation of numbers is similar to that used in most + > programming languages. A number is represented in base 10 using decimal + > digits. It contains an integer component that may be prefixed with an + > optional minus sign, which may be followed by a fraction part and/or an + > exponent part. Leading zeros are not allowed. (...) Numeric values that + > cannot be represented in the grammar below (such as Infinity and NaN) + > are not permitted. + + This description includes both integer and floating-point numbers. + However, C++ allows more precise storage if it is known whether the number + is a signed integer, an unsigned integer or a floating-point number. + Therefore, three different types, @ref number_integer_t, @ref + number_unsigned_t and @ref number_float_t are used. + + To store integer numbers in C++, a type is defined by the template + parameter @a NumberIntegerType which chooses the type to use. + + #### Default type + + With the default values for @a NumberIntegerType (`int64_t`), the default + value for @a number_integer_t is: + + @code {.cpp} + int64_t + @endcode + + #### Default behavior + + - The restrictions about leading zeros is not enforced in C++. Instead, + leading zeros in integer literals lead to an interpretation as octal + number. Internally, the value will be stored as decimal number. For + instance, the C++ integer literal `010` will be serialized to `8`. + During deserialization, leading zeros yield an error. + - Not-a-number (NaN) values will be serialized to `null`. + + #### Limits + + [RFC 7159](http://rfc7159.net/rfc7159) specifies: + > An implementation may set limits on the range and precision of numbers. + + When the default type is used, the maximal integer number that can be + stored is `9223372036854775807` (INT64_MAX) and the minimal integer number + that can be stored is `-9223372036854775808` (INT64_MIN). Integer numbers + that are out of range will yield over/underflow when used in a + constructor. During deserialization, too large or small integer numbers + will be automatically be stored as @ref number_unsigned_t or @ref + number_float_t. + + [RFC 7159](http://rfc7159.net/rfc7159) further states: + > Note that when such software is used, numbers that are integers and are + > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense + > that implementations will agree exactly on their numeric values. + + As this range is a subrange of the exactly supported range [INT64_MIN, + INT64_MAX], this class's integer type is interoperable. + + #### Storage + + Integer number values are stored directly inside a @ref basic_json type. + + @sa @ref number_float_t -- type for number values (floating-point) + + @sa @ref number_unsigned_t -- type for number values (unsigned integer) + + @since version 1.0.0 + */ + using number_integer_t = NumberIntegerType; + + /*! + @brief a type for a number (unsigned) + + [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows: + > The representation of numbers is similar to that used in most + > programming languages. A number is represented in base 10 using decimal + > digits. It contains an integer component that may be prefixed with an + > optional minus sign, which may be followed by a fraction part and/or an + > exponent part. Leading zeros are not allowed. (...) Numeric values that + > cannot be represented in the grammar below (such as Infinity and NaN) + > are not permitted. + + This description includes both integer and floating-point numbers. + However, C++ allows more precise storage if it is known whether the number + is a signed integer, an unsigned integer or a floating-point number. + Therefore, three different types, @ref number_integer_t, @ref + number_unsigned_t and @ref number_float_t are used. + + To store unsigned integer numbers in C++, a type is defined by the + template parameter @a NumberUnsignedType which chooses the type to use. + + #### Default type + + With the default values for @a NumberUnsignedType (`uint64_t`), the + default value for @a number_unsigned_t is: + + @code {.cpp} + uint64_t + @endcode + + #### Default behavior + + - The restrictions about leading zeros is not enforced in C++. Instead, + leading zeros in integer literals lead to an interpretation as octal + number. Internally, the value will be stored as decimal number. For + instance, the C++ integer literal `010` will be serialized to `8`. + During deserialization, leading zeros yield an error. + - Not-a-number (NaN) values will be serialized to `null`. + + #### Limits + + [RFC 7159](http://rfc7159.net/rfc7159) specifies: + > An implementation may set limits on the range and precision of numbers. + + When the default type is used, the maximal integer number that can be + stored is `18446744073709551615` (UINT64_MAX) and the minimal integer + number that can be stored is `0`. Integer numbers that are out of range + will yield over/underflow when used in a constructor. During + deserialization, too large or small integer numbers will be automatically + be stored as @ref number_integer_t or @ref number_float_t. + + [RFC 7159](http://rfc7159.net/rfc7159) further states: + > Note that when such software is used, numbers that are integers and are + > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense + > that implementations will agree exactly on their numeric values. + + As this range is a subrange (when considered in conjunction with the + number_integer_t type) of the exactly supported range [0, UINT64_MAX], + this class's integer type is interoperable. + + #### Storage + + Integer number values are stored directly inside a @ref basic_json type. + + @sa @ref number_float_t -- type for number values (floating-point) + @sa @ref number_integer_t -- type for number values (integer) + + @since version 2.0.0 + */ + using number_unsigned_t = NumberUnsignedType; /*! - @brief the JSON type enumeration + @brief a type for a number (floating-point) + + [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows: + > The representation of numbers is similar to that used in most + > programming languages. A number is represented in base 10 using decimal + > digits. It contains an integer component that may be prefixed with an + > optional minus sign, which may be followed by a fraction part and/or an + > exponent part. Leading zeros are not allowed. (...) Numeric values that + > cannot be represented in the grammar below (such as Infinity and NaN) + > are not permitted. + + This description includes both integer and floating-point numbers. + However, C++ allows more precise storage if it is known whether the number + is a signed integer, an unsigned integer or a floating-point number. + Therefore, three different types, @ref number_integer_t, @ref + number_unsigned_t and @ref number_float_t are used. + + To store floating-point numbers in C++, a type is defined by the template + parameter @a NumberFloatType which chooses the type to use. + + #### Default type + + With the default values for @a NumberFloatType (`double`), the default + value for @a number_float_t is: + + @code {.cpp} + double + @endcode + + #### Default behavior - This enumeration collects the different JSON types. It is internally used - to distinguish the stored values, and the functions @ref is_null(), @ref - is_object(), @ref is_array(), @ref is_string(), @ref is_boolean(), @ref - is_number() (with @ref is_number_integer(), @ref is_number_unsigned(), and - @ref is_number_float()), @ref is_discarded(), @ref is_primitive(), and - @ref is_structured() rely on it. + - The restrictions about leading zeros is not enforced in C++. Instead, + leading zeros in floating-point literals will be ignored. Internally, + the value will be stored as decimal number. For instance, the C++ + floating-point literal `01.2` will be serialized to `1.2`. During + deserialization, leading zeros yield an error. + - Not-a-number (NaN) values will be serialized to `null`. + + #### Limits + + [RFC 7159](http://rfc7159.net/rfc7159) states: + > This specification allows implementations to set limits on the range and + > precision of numbers accepted. Since software that implements IEEE + > 754-2008 binary64 (double precision) numbers is generally available and + > widely used, good interoperability can be achieved by implementations + > that expect no more precision or range than these provide, in the sense + > that implementations will approximate JSON numbers within the expected + > precision. + + This implementation does exactly follow this approach, as it uses double + precision floating-point numbers. Note values smaller than + `-1.79769313486232e+308` and values greater than `1.79769313486232e+308` + will be stored as NaN internally and be serialized to `null`. + + #### Storage - @note There are three enumeration entries (number_integer, - number_unsigned, and number_float), because the library distinguishes - these three types for numbers: @ref number_unsigned_t is used for unsigned - integers, @ref number_integer_t is used for signed integers, and @ref - number_float_t is used for floating-point numbers or to approximate - integers which do not fit in the limits of their respective type. + Floating-point number values are stored directly inside a @ref basic_json + type. + + @sa @ref number_integer_t -- type for number values (integer) - @sa @ref basic_json(const value_t value_type) -- create a JSON value with - the default value for a given type + @sa @ref number_unsigned_t -- type for number values (unsigned integer) @since version 1.0.0 */ - enum class value_t : uint8_t - { - null, ///< null value - object, ///< object (unordered set of name/value pairs) - array, ///< array (ordered collection of values) - string, ///< string value - boolean, ///< boolean value - number_integer, ///< number value (signed integer) - number_unsigned, ///< number value (unsigned integer) - number_float, ///< number value (floating-point) - discarded ///< discarded by the the parser callback function - }; + using number_float_t = NumberFloatType; + /// @} private: @@ -760,7 +1913,7 @@ class basic_json }; std::unique_ptr object(alloc.allocate(1), deleter); alloc.construct(object.get(), std::forward(args)...); - assert(object.get() != nullptr); + assert(object != nullptr); return object.release(); } @@ -866,8 +2019,17 @@ class basic_json break; } + case value_t::null: + { + break; + } + default: { + if (JSON_UNLIKELY(t == value_t::null)) + { + JSON_THROW(other_error::create(500, "961c151d2e87f2686a955a9be24d316f1362bf21 2.1.1")); // LCOV_EXCL_LINE + } break; } } @@ -944,7 +2106,7 @@ class basic_json With a parser callback function, the result of parsing a JSON text can be influenced. When passed to @ref parse(std::istream&, const - parser_callback_t) or @ref parse(const char*, const parser_callback_t), + parser_callback_t) or @ref parse(const CharT, const parser_callback_t), it is called on certain events (passed as @ref parse_event_t via parameter @a event) with a set recursion depth @a depth and context JSON value @a parsed. The return value of the callback function is a boolean @@ -987,7 +2149,7 @@ class basic_json skipped completely or replaced by an empty discarded object. @sa @ref parse(std::istream&, parser_callback_t) or - @ref parse(const char*, parser_callback_t) for examples + @ref parse(const CharT, const parser_callback_t) for examples @since version 1.0.0 */ @@ -1024,24 +2186,9 @@ class basic_json @complexity Constant. - @throw std::bad_alloc if allocation for object, array, or string value - fails - @liveexample{The following code shows the constructor for different @ref value_t values,basic_json__value_t} - @sa @ref basic_json(std::nullptr_t) -- create a `null` value - @sa @ref basic_json(boolean_t value) -- create a boolean value - @sa @ref basic_json(const string_t&) -- create a string value - @sa @ref basic_json(const object_t&) -- create a object value - @sa @ref basic_json(const array_t&) -- create a array value - @sa @ref basic_json(const number_float_t) -- create a number - (floating-point) value - @sa @ref basic_json(const number_integer_t) -- create a number (integer) - value - @sa @ref basic_json(const number_unsigned_t) -- create a number (unsigned) - value - @since version 1.0.0 */ basic_json(const value_t value_type) @@ -1075,6640 +2222,8794 @@ class basic_json } /*! - @brief create an object (explicit) + @brief create a JSON value - Create an object JSON value with a given content. + This is a "catch all" constructor for all compatible JSON types; that is, + types for which a `to_json()` method exsits. The constructor forwards the + parameter @a val to that method (to `json_serializer::to_json` method + with `U = uncvref_t`, to be exact). - @param[in] val a value for the object + Template type @a CompatibleType includes, but is not limited to, the + following types: + - **arrays**: @ref array_t and all kinds of compatible containers such as + `std::vector`, `std::deque`, `std::list`, `std::forward_list`, + `std::array`, `std::set`, `std::unordered_set`, `std::multiset`, and + `unordered_multiset` with a `value_type` from which a @ref basic_json + value can be constructed. + - **objects**: @ref object_t and all kinds of compatible associative + containers such as `std::map`, `std::unordered_map`, `std::multimap`, + and `std::unordered_multimap` with a `key_type` compatible to + @ref string_t and a `value_type` from which a @ref basic_json value can + be constructed. + - **strings**: @ref string_t, string literals, and all compatible string + containers can be used. + - **numbers**: @ref number_integer_t, @ref number_unsigned_t, + @ref number_float_t, and all convertible number types such as `int`, + `size_t`, `int64_t`, `float` or `double` can be used. + - **boolean**: @ref boolean_t / `bool` can be used. - @complexity Linear in the size of the passed @a val. + See the examples below. - @throw std::bad_alloc if allocation for object value fails + @tparam CompatibleType a type such that: + - @a CompatibleType is not derived from `std::istream`, + - @a CompatibleType is not @ref basic_json (to avoid hijacking copy/move + constructors), + - @a CompatibleType is not a @ref basic_json nested type (e.g., + @ref json_pointer, @ref iterator, etc ...) + - @ref @ref json_serializer has a + `to_json(basic_json_t&, CompatibleType&&)` method - @liveexample{The following code shows the constructor with an @ref - object_t parameter.,basic_json__object_t} + @tparam U = `uncvref_t` - @sa @ref basic_json(const CompatibleObjectType&) -- create an object value - from a compatible STL container + @param[in] val the value to be forwarded - @since version 1.0.0 + @complexity Usually linear in the size of the passed @a val, also + depending on the implementation of the called `to_json()` + method. + + @throw what `json_serializer::to_json()` throws + + @liveexample{The following code shows the constructor with several + compatible types.,basic_json__CompatibleType} + + @since version 2.1.0 */ - basic_json(const object_t& val) - : m_type(value_t::object), m_value(val) + template, + detail::enable_if_t::value and + not std::is_same::value and + not detail::is_basic_json_nested_type< + basic_json_t, U>::value and + detail::has_to_json::value, + int> = 0> + basic_json(CompatibleType && val) noexcept(noexcept(JSONSerializer::to_json( + std::declval(), std::forward(val)))) { + JSONSerializer::to_json(*this, std::forward(val)); assert_invariant(); } /*! - @brief create an object (implicit) + @brief create a container (array or object) from an initializer list + + Creates a JSON value of type array or object from the passed initializer + list @a init. In case @a type_deduction is `true` (default), the type of + the JSON value to be created is deducted from the initializer list @a init + according to the following rules: + + 1. If the list is empty, an empty JSON object value `{}` is created. + 2. If the list consists of pairs whose first element is a string, a JSON + object value is created where the first elements of the pairs are + treated as keys and the second elements are as values. + 3. In all other cases, an array is created. + + The rules aim to create the best fit between a C++ initializer list and + JSON values. The rationale is as follows: + + 1. The empty initializer list is written as `{}` which is exactly an empty + JSON object. + 2. C++ has now way of describing mapped types other than to list a list of + pairs. As JSON requires that keys must be of type string, rule 2 is the + weakest constraint one can pose on initializer lists to interpret them + as an object. + 3. In all other cases, the initializer list could not be interpreted as + JSON object type, so interpreting it as JSON array type is safe. + + With the rules described above, the following JSON values cannot be + expressed by an initializer list: + + - the empty array (`[]`): use @ref array(std::initializer_list) + with an empty initializer list in this case + - arrays whose elements satisfy rule 2: use @ref + array(std::initializer_list) with the same initializer list + in this case + + @note When used without parentheses around an empty initializer list, @ref + basic_json() is called instead of this function, yielding the JSON null + value. - Create an object JSON value with a given content. This constructor allows - any type @a CompatibleObjectType that can be used to construct values of - type @ref object_t. + @param[in] init initializer list with JSON values - @tparam CompatibleObjectType An object type whose `key_type` and - `value_type` is compatible to @ref object_t. Examples include `std::map`, - `std::unordered_map`, `std::multimap`, and `std::unordered_multimap` with - a `key_type` of `std::string`, and a `value_type` from which a @ref - basic_json value can be constructed. + @param[in] type_deduction internal parameter; when set to `true`, the type + of the JSON value is deducted from the initializer list @a init; when set + to `false`, the type provided via @a manual_type is forced. This mode is + used by the functions @ref array(std::initializer_list) and + @ref object(std::initializer_list). - @param[in] val a value for the object + @param[in] manual_type internal parameter; when @a type_deduction is set + to `false`, the created JSON value will use the provided type (only @ref + value_t::array and @ref value_t::object are valid); when @a type_deduction + is set to `true`, this parameter has no effect - @complexity Linear in the size of the passed @a val. + @throw type_error.301 if @a type_deduction is `false`, @a manual_type is + `value_t::object`, but @a init contains an element which is not a pair + whose first element is a string. In this case, the constructor could not + create an object. If @a type_deduction would have be `true`, an array + would have been created. See @ref object(std::initializer_list) + for an example. - @throw std::bad_alloc if allocation for object value fails + @complexity Linear in the size of the initializer list @a init. - @liveexample{The following code shows the constructor with several - compatible object type parameters.,basic_json__CompatibleObjectType} + @liveexample{The example below shows how JSON values are created from + initializer lists.,basic_json__list_init_t} - @sa @ref basic_json(const object_t&) -- create an object value + @sa @ref array(std::initializer_list) -- create a JSON array + value from an initializer list + @sa @ref object(std::initializer_list) -- create a JSON object + value from an initializer list @since version 1.0.0 */ - template::value and - std::is_constructible::value, int>::type = 0> - basic_json(const CompatibleObjectType& val) - : m_type(value_t::object) + basic_json(std::initializer_list init, + bool type_deduction = true, + value_t manual_type = value_t::array) { - using std::begin; - using std::end; - m_value.object = create(begin(val), end(val)); + // check if each element is an array with two elements whose first + // element is a string + bool is_an_object = std::all_of(init.begin(), init.end(), + [](const basic_json & element) + { + return element.is_array() and element.size() == 2 and element[0].is_string(); + }); + + // adjust type if type deduction is not wanted + if (not type_deduction) + { + // if array is wanted, do not create an object though possible + if (manual_type == value_t::array) + { + is_an_object = false; + } + + // if object is wanted but impossible, throw an exception + if (manual_type == value_t::object and not is_an_object) + { + JSON_THROW(type_error::create(301, "cannot create object from initializer list")); + } + } + + if (is_an_object) + { + // the initializer list is a list of pairs -> create object + m_type = value_t::object; + m_value = value_t::object; + + std::for_each(init.begin(), init.end(), [this](const basic_json & element) + { + m_value.object->emplace(*(element[0].m_value.string), element[1]); + }); + } + else + { + // the initializer list describes an array -> create array + m_type = value_t::array; + m_value.array = create(init); + } + assert_invariant(); } /*! - @brief create an array (explicit) + @brief explicitly create an array from an initializer list + + Creates a JSON array value from a given initializer list. That is, given a + list of values `a, b, c`, creates the JSON value `[a, b, c]`. If the + initializer list is empty, the empty array `[]` is created. - Create an array JSON value with a given content. + @note This function is only needed to express two edge cases that cannot + be realized with the initializer list constructor (@ref + basic_json(std::initializer_list, bool, value_t)). These cases + are: + 1. creating an array whose elements are all pairs whose first element is a + string -- in this case, the initializer list constructor would create an + object, taking the first elements as keys + 2. creating an empty array -- passing the empty initializer list to the + initializer list constructor yields an empty object - @param[in] val a value for the array + @param[in] init initializer list with JSON values to create an array from + (optional) - @complexity Linear in the size of the passed @a val. + @return JSON array value - @throw std::bad_alloc if allocation for array value fails + @complexity Linear in the size of @a init. - @liveexample{The following code shows the constructor with an @ref array_t - parameter.,basic_json__array_t} + @liveexample{The following code shows an example for the `array` + function.,array} - @sa @ref basic_json(const CompatibleArrayType&) -- create an array value - from a compatible STL containers + @sa @ref basic_json(std::initializer_list, bool, value_t) -- + create a JSON value from an initializer list + @sa @ref object(std::initializer_list) -- create a JSON object + value from an initializer list @since version 1.0.0 */ - basic_json(const array_t& val) - : m_type(value_t::array), m_value(val) + static basic_json array(std::initializer_list init = + std::initializer_list()) { - assert_invariant(); + return basic_json(init, false, value_t::array); } /*! - @brief create an array (implicit) + @brief explicitly create an object from an initializer list - Create an array JSON value with a given content. This constructor allows - any type @a CompatibleArrayType that can be used to construct values of - type @ref array_t. + Creates a JSON object value from a given initializer list. The initializer + lists elements must be pairs, and their first elements must be strings. If + the initializer list is empty, the empty object `{}` is created. + + @note This function is only added for symmetry reasons. In contrast to the + related function @ref array(std::initializer_list), there are + no cases which can only be expressed by this function. That is, any + initializer list @a init can also be passed to the initializer list + constructor @ref basic_json(std::initializer_list, bool, value_t). - @tparam CompatibleArrayType An object type whose `value_type` is - compatible to @ref array_t. Examples include `std::vector`, `std::deque`, - `std::list`, `std::forward_list`, `std::array`, `std::set`, - `std::unordered_set`, `std::multiset`, and `unordered_multiset` with a - `value_type` from which a @ref basic_json value can be constructed. + @param[in] init initializer list to create an object from (optional) - @param[in] val a value for the array + @return JSON object value - @complexity Linear in the size of the passed @a val. + @throw type_error.301 if @a init is not a list of pairs whose first + elements are strings. In this case, no object can be created. When such a + value is passed to @ref basic_json(std::initializer_list, bool, value_t), + an array would have been created from the passed initializer list @a init. + See example below. - @throw std::bad_alloc if allocation for array value fails + @complexity Linear in the size of @a init. - @liveexample{The following code shows the constructor with several - compatible array type parameters.,basic_json__CompatibleArrayType} + @liveexample{The following code shows an example for the `object` + function.,object} - @sa @ref basic_json(const array_t&) -- create an array value + @sa @ref basic_json(std::initializer_list, bool, value_t) -- + create a JSON value from an initializer list + @sa @ref array(std::initializer_list) -- create a JSON array + value from an initializer list @since version 1.0.0 */ - template::value and - not std::is_same::value and - not std::is_same::value and - not std::is_same::value and - not std::is_same::value and - not std::is_same::value and - std::is_constructible::value, int>::type = 0> - basic_json(const CompatibleArrayType& val) - : m_type(value_t::array) + static basic_json object(std::initializer_list init = + std::initializer_list()) { - using std::begin; - using std::end; - m_value.array = create(begin(val), end(val)); - assert_invariant(); + return basic_json(init, false, value_t::object); } /*! - @brief create a string (explicit) - - Create an string JSON value with a given content. - - @param[in] val a value for the string + @brief construct an array with count copies of given value - @complexity Linear in the size of the passed @a val. + Constructs a JSON array value by creating @a cnt copies of a passed value. + In case @a cnt is `0`, an empty array is created. As postcondition, + `std::distance(begin(),end()) == cnt` holds. - @throw std::bad_alloc if allocation for string value fails + @param[in] cnt the number of JSON copies of @a val to create + @param[in] val the JSON value to copy - @liveexample{The following code shows the constructor with an @ref - string_t parameter.,basic_json__string_t} + @complexity Linear in @a cnt. - @sa @ref basic_json(const typename string_t::value_type*) -- create a - string value from a character pointer - @sa @ref basic_json(const CompatibleStringType&) -- create a string value - from a compatible string container + @liveexample{The following code shows examples for the @ref + basic_json(size_type\, const basic_json&) + constructor.,basic_json__size_type_basic_json} @since version 1.0.0 */ - basic_json(const string_t& val) - : m_type(value_t::string), m_value(val) + basic_json(size_type cnt, const basic_json& val) + : m_type(value_t::array) { + m_value.array = create(cnt, val); assert_invariant(); } /*! - @brief create a string (explicit) + @brief construct a JSON container given an iterator range + + Constructs the JSON value with the contents of the range `[first, last)`. + The semantics depends on the different types a JSON value can have: + - In case of primitive types (number, boolean, or string), @a first must + be `begin()` and @a last must be `end()`. In this case, the value is + copied. Otherwise, invalid_iterator.204 is thrown. + - In case of structured types (array, object), the constructor behaves as + similar versions for `std::vector`. + - In case of a null type, invalid_iterator.206 is thrown. - Create a string JSON value with a given content. + @tparam InputIT an input iterator type (@ref iterator or @ref + const_iterator) + + @param[in] first begin of the range to copy from (included) + @param[in] last end of the range to copy from (excluded) - @param[in] val a literal value for the string + @pre Iterators @a first and @a last must be initialized. **This + precondition is enforced with an assertion.** - @complexity Linear in the size of the passed @a val. + @pre Range `[first, last)` is valid. Usually, this precondition cannot be + checked efficiently. Only certain edge cases are detected; see the + description of the exceptions below. - @throw std::bad_alloc if allocation for string value fails + @throw invalid_iterator.201 if iterators @a first and @a last are not + compatible (i.e., do not belong to the same JSON value). In this case, + the range `[first, last)` is undefined. + @throw invalid_iterator.204 if iterators @a first and @a last belong to a + primitive type (number, boolean, or string), but @a first does not point + to the first element any more. In this case, the range `[first, last)` is + undefined. See example code below. + @throw invalid_iterator.206 if iterators @a first and @a last belong to a + null value. In this case, the range `[first, last)` is undefined. - @liveexample{The following code shows the constructor with string literal - parameter.,basic_json__string_t_value_type} + @complexity Linear in distance between @a first and @a last. - @sa @ref basic_json(const string_t&) -- create a string value - @sa @ref basic_json(const CompatibleStringType&) -- create a string value - from a compatible string container + @liveexample{The example below shows several ways to create JSON values by + specifying a subrange with iterators.,basic_json__InputIt_InputIt} @since version 1.0.0 */ - basic_json(const typename string_t::value_type* val) - : basic_json(string_t(val)) + template::value or + std::is_same::value, int>::type = 0> + basic_json(InputIT first, InputIT last) { - assert_invariant(); - } + assert(first.m_object != nullptr); + assert(last.m_object != nullptr); - /*! - @brief create a string (implicit) + // make sure iterator fits the current value + if (first.m_object != last.m_object) + { + JSON_THROW(invalid_iterator::create(201, "iterators are not compatible")); + } + + // copy type from first iterator + m_type = first.m_object->m_type; + + // check if iterator range is complete for primitive values + switch (m_type) + { + case value_t::boolean: + case value_t::number_float: + case value_t::number_integer: + case value_t::number_unsigned: + case value_t::string: + { + if (not first.m_it.primitive_iterator.is_begin() or not last.m_it.primitive_iterator.is_end()) + { + JSON_THROW(invalid_iterator::create(204, "iterators out of range")); + } + break; + } + + default: + { + break; + } + } + + switch (m_type) + { + case value_t::number_integer: + { + m_value.number_integer = first.m_object->m_value.number_integer; + break; + } - Create a string JSON value with a given content. + case value_t::number_unsigned: + { + m_value.number_unsigned = first.m_object->m_value.number_unsigned; + break; + } - @param[in] val a value for the string + case value_t::number_float: + { + m_value.number_float = first.m_object->m_value.number_float; + break; + } - @tparam CompatibleStringType an string type which is compatible to @ref - string_t, for instance `std::string`. + case value_t::boolean: + { + m_value.boolean = first.m_object->m_value.boolean; + break; + } - @complexity Linear in the size of the passed @a val. + case value_t::string: + { + m_value = *first.m_object->m_value.string; + break; + } - @throw std::bad_alloc if allocation for string value fails + case value_t::object: + { + m_value.object = create(first.m_it.object_iterator, + last.m_it.object_iterator); + break; + } - @liveexample{The following code shows the construction of a string value - from a compatible type.,basic_json__CompatibleStringType} + case value_t::array: + { + m_value.array = create(first.m_it.array_iterator, + last.m_it.array_iterator); + break; + } - @sa @ref basic_json(const string_t&) -- create a string value - @sa @ref basic_json(const typename string_t::value_type*) -- create a - string value from a character pointer + default: + { + JSON_THROW(invalid_iterator::create(206, "cannot construct with iterators from " + + first.m_object->type_name())); + } + } - @since version 1.0.0 - */ - template::value, int>::type = 0> - basic_json(const CompatibleStringType& val) - : basic_json(string_t(val)) - { assert_invariant(); } + + /////////////////////////////////////// + // other constructors and destructor // + /////////////////////////////////////// + /*! - @brief create a boolean (explicit) + @brief copy constructor - Creates a JSON boolean type from a given value. + Creates a copy of a given JSON value. - @param[in] val a boolean value to store + @param[in] other the JSON value to copy - @complexity Constant. + @complexity Linear in the size of @a other. + + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is linear. + - As postcondition, it holds: `other == basic_json(other)`. - @liveexample{The example below demonstrates boolean - values.,basic_json__boolean_t} + @liveexample{The following code shows an example for the copy + constructor.,basic_json__basic_json} @since version 1.0.0 */ - basic_json(boolean_t val) noexcept - : m_type(value_t::boolean), m_value(val) + basic_json(const basic_json& other) + : m_type(other.m_type) { - assert_invariant(); - } + // check of passed value is valid + other.assert_invariant(); - /*! - @brief create an integer number (explicit) + switch (m_type) + { + case value_t::object: + { + m_value = *other.m_value.object; + break; + } + + case value_t::array: + { + m_value = *other.m_value.array; + break; + } - Create an integer number JSON value with a given content. + case value_t::string: + { + m_value = *other.m_value.string; + break; + } - @tparam T A helper type to remove this function via SFINAE in case @ref - number_integer_t is the same as `int`. In this case, this constructor - would have the same signature as @ref basic_json(const int value). Note - the helper type @a T is not visible in this constructor's interface. + case value_t::boolean: + { + m_value = other.m_value.boolean; + break; + } - @param[in] val an integer to create a JSON number from + case value_t::number_integer: + { + m_value = other.m_value.number_integer; + break; + } - @complexity Constant. + case value_t::number_unsigned: + { + m_value = other.m_value.number_unsigned; + break; + } - @liveexample{The example below shows the construction of an integer - number value.,basic_json__number_integer_t} + case value_t::number_float: + { + m_value = other.m_value.number_float; + break; + } - @sa @ref basic_json(const int) -- create a number value (integer) - @sa @ref basic_json(const CompatibleNumberIntegerType) -- create a number - value (integer) from a compatible number type + default: + { + break; + } + } - @since version 1.0.0 - */ - template::value) and - std::is_same::value, int>::type = 0> - basic_json(const number_integer_t val) noexcept - : m_type(value_t::number_integer), m_value(val) - { assert_invariant(); } /*! - @brief create an integer number from an enum type (explicit) + @brief move constructor - Create an integer number JSON value with a given content. + Move constructor. Constructs a JSON value with the contents of the given + value @a other using move semantics. It "steals" the resources from @a + other and leaves it as JSON null value. - @param[in] val an integer to create a JSON number from + @param[in,out] other value to move to this object - @note This constructor allows to pass enums directly to a constructor. As - C++ has no way of specifying the type of an anonymous enum explicitly, we - can only rely on the fact that such values implicitly convert to int. As - int may already be the same type of number_integer_t, we may need to - switch off the constructor @ref basic_json(const number_integer_t). + @post @a other is a JSON null value @complexity Constant. - @liveexample{The example below shows the construction of an integer - number value from an anonymous enum.,basic_json__const_int} - - @sa @ref basic_json(const number_integer_t) -- create a number value - (integer) - @sa @ref basic_json(const CompatibleNumberIntegerType) -- create a number - value (integer) from a compatible number type + @liveexample{The code below shows the move constructor explicitly called + via std::move.,basic_json__moveconstructor} @since version 1.0.0 */ - basic_json(const int val) noexcept - : m_type(value_t::number_integer), - m_value(static_cast(val)) + basic_json(basic_json&& other) noexcept + : m_type(std::move(other.m_type)), + m_value(std::move(other.m_value)) { + // check that passed value is valid + other.assert_invariant(); + + // invalidate payload + other.m_type = value_t::null; + other.m_value = {}; + assert_invariant(); } /*! - @brief create an integer number (implicit) - - Create an integer number JSON value with a given content. This constructor - allows any type @a CompatibleNumberIntegerType that can be used to - construct values of type @ref number_integer_t. + @brief copy assignment - @tparam CompatibleNumberIntegerType An integer type which is compatible to - @ref number_integer_t. Examples include the types `int`, `int32_t`, - `long`, and `short`. + Copy assignment operator. Copies a JSON value via the "copy and swap" + strategy: It is expressed in terms of the copy constructor, destructor, + and the swap() member function. - @param[in] val an integer to create a JSON number from + @param[in] other value to copy from - @complexity Constant. + @complexity Linear. - @liveexample{The example below shows the construction of several integer - number values from compatible - types.,basic_json__CompatibleIntegerNumberType} + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is linear. - @sa @ref basic_json(const number_integer_t) -- create a number value - (integer) - @sa @ref basic_json(const int) -- create a number value (integer) + @liveexample{The code below shows and example for the copy assignment. It + creates a copy of value `a` which is then swapped with `b`. Finally\, the + copy of `a` (which is the null value after the swap) is + destroyed.,basic_json__copyassignment} @since version 1.0.0 */ - template::value and - std::numeric_limits::is_integer and - std::numeric_limits::is_signed, - CompatibleNumberIntegerType>::type = 0> - basic_json(const CompatibleNumberIntegerType val) noexcept - : m_type(value_t::number_integer), - m_value(static_cast(val)) + reference& operator=(basic_json other) noexcept ( + std::is_nothrow_move_constructible::value and + std::is_nothrow_move_assignable::value and + std::is_nothrow_move_constructible::value and + std::is_nothrow_move_assignable::value + ) { + // check that passed value is valid + other.assert_invariant(); + + using std::swap; + swap(m_type, other.m_type); + swap(m_value, other.m_value); + assert_invariant(); + return *this; } /*! - @brief create an unsigned integer number (explicit) - - Create an unsigned integer number JSON value with a given content. - - @tparam T helper type to compare number_unsigned_t and unsigned int (not - visible in) the interface. + @brief destructor - @param[in] val an integer to create a JSON number from + Destroys the JSON value and frees all allocated memory. - @complexity Constant. + @complexity Linear. - @sa @ref basic_json(const CompatibleNumberUnsignedType) -- create a number - value (unsigned integer) from a compatible number type + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is linear. + - All stored elements are destroyed and all memory is freed. - @since version 2.0.0 + @since version 1.0.0 */ - template::value) and - std::is_same::value, int>::type = 0> - basic_json(const number_unsigned_t val) noexcept - : m_type(value_t::number_unsigned), m_value(val) + ~basic_json() { assert_invariant(); - } - /*! - @brief create an unsigned number (implicit) + switch (m_type) + { + case value_t::object: + { + AllocatorType alloc; + alloc.destroy(m_value.object); + alloc.deallocate(m_value.object, 1); + break; + } - Create an unsigned number JSON value with a given content. This - constructor allows any type @a CompatibleNumberUnsignedType that can be - used to construct values of type @ref number_unsigned_t. + case value_t::array: + { + AllocatorType alloc; + alloc.destroy(m_value.array); + alloc.deallocate(m_value.array, 1); + break; + } - @tparam CompatibleNumberUnsignedType An integer type which is compatible - to @ref number_unsigned_t. Examples may include the types `unsigned int`, - `uint32_t`, or `unsigned short`. + case value_t::string: + { + AllocatorType alloc; + alloc.destroy(m_value.string); + alloc.deallocate(m_value.string, 1); + break; + } - @param[in] val an unsigned integer to create a JSON number from + default: + { + // all other types need no specific destructor + break; + } + } + } - @complexity Constant. + /// @} - @sa @ref basic_json(const number_unsigned_t) -- create a number value - (unsigned) + public: + /////////////////////// + // object inspection // + /////////////////////// - @since version 2.0.0 - */ - template::value and - std::numeric_limits::is_integer and - not std::numeric_limits::is_signed, - CompatibleNumberUnsignedType>::type = 0> - basic_json(const CompatibleNumberUnsignedType val) noexcept - : m_type(value_t::number_unsigned), - m_value(static_cast(val)) - { - assert_invariant(); - } + /// @name object inspection + /// Functions to inspect the type of a JSON value. + /// @{ /*! - @brief create a floating-point number (explicit) + @brief serialization - Create a floating-point number JSON value with a given content. + Serialization function for JSON values. The function tries to mimic + Python's `json.dumps()` function, and currently supports its @a indent + parameter. - @param[in] val a floating-point value to create a JSON number from + @param[in] indent If indent is nonnegative, then array elements and object + members will be pretty-printed with that indent level. An indent level of + `0` will only insert newlines. `-1` (the default) selects the most compact + representation. + @param[in] indent_char The character to use for indentation of @a indent is + greate than `0`. The default is ` ` (space). - @note [RFC 7159](http://www.rfc-editor.org/rfc/rfc7159.txt), section 6 - disallows NaN values: - > Numeric values that cannot be represented in the grammar below (such as - > Infinity and NaN) are not permitted. - In case the parameter @a val is not a number, a JSON null value is created - instead. + @return string containing the serialization of the JSON value - @complexity Constant. + @complexity Linear. - @liveexample{The following example creates several floating-point - values.,basic_json__number_float_t} + @liveexample{The following example shows the effect of different @a indent + parameters to the result of the serialization.,dump} - @sa @ref basic_json(const CompatibleNumberFloatType) -- create a number - value (floating-point) from a compatible number type + @see https://docs.python.org/2/library/json.html#json.dump - @since version 1.0.0 + @since version 1.0.0; indentaction character added in version 3.0.0 */ - basic_json(const number_float_t val) noexcept - : m_type(value_t::number_float), m_value(val) + string_t dump(const int indent = -1, const char indent_char = ' ') const { - // replace infinity and NAN by null - if (not std::isfinite(val)) + string_t result; + serializer s(output_adapter::create(result), indent_char); + + if (indent >= 0) { - m_type = value_t::null; - m_value = json_value(); + s.dump(*this, true, static_cast(indent)); + } + else + { + s.dump(*this, false, 0); } - assert_invariant(); + return result; } /*! - @brief create an floating-point number (implicit) - - Create an floating-point number JSON value with a given content. This - constructor allows any type @a CompatibleNumberFloatType that can be used - to construct values of type @ref number_float_t. - - @tparam CompatibleNumberFloatType A floating-point type which is - compatible to @ref number_float_t. Examples may include the types `float` - or `double`. + @brief return the type of the JSON value (explicit) - @param[in] val a floating-point to create a JSON number from + Return the type of the JSON value as a value from the @ref value_t + enumeration. - @note [RFC 7159](http://www.rfc-editor.org/rfc/rfc7159.txt), section 6 - disallows NaN values: - > Numeric values that cannot be represented in the grammar below (such as - > Infinity and NaN) are not permitted. - In case the parameter @a val is not a number, a JSON null value is - created instead. + @return the type of the JSON value @complexity Constant. - @liveexample{The example below shows the construction of several - floating-point number values from compatible - types.,basic_json__CompatibleNumberFloatType} + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - @sa @ref basic_json(const number_float_t) -- create a number value - (floating-point) + @liveexample{The following code exemplifies `type()` for all JSON + types.,type} @since version 1.0.0 */ - template::value and - std::is_floating_point::value>::type> - basic_json(const CompatibleNumberFloatType val) noexcept - : basic_json(number_float_t(val)) + constexpr value_t type() const noexcept { - assert_invariant(); + return m_type; } /*! - @brief create a container (array or object) from an initializer list - - Creates a JSON value of type array or object from the passed initializer - list @a init. In case @a type_deduction is `true` (default), the type of - the JSON value to be created is deducted from the initializer list @a init - according to the following rules: - - 1. If the list is empty, an empty JSON object value `{}` is created. - 2. If the list consists of pairs whose first element is a string, a JSON - object value is created where the first elements of the pairs are - treated as keys and the second elements are as values. - 3. In all other cases, an array is created. - - The rules aim to create the best fit between a C++ initializer list and - JSON values. The rationale is as follows: - - 1. The empty initializer list is written as `{}` which is exactly an empty - JSON object. - 2. C++ has now way of describing mapped types other than to list a list of - pairs. As JSON requires that keys must be of type string, rule 2 is the - weakest constraint one can pose on initializer lists to interpret them - as an object. - 3. In all other cases, the initializer list could not be interpreted as - JSON object type, so interpreting it as JSON array type is safe. - - With the rules described above, the following JSON values cannot be - expressed by an initializer list: - - - the empty array (`[]`): use @ref array(std::initializer_list) - with an empty initializer list in this case - - arrays whose elements satisfy rule 2: use @ref - array(std::initializer_list) with the same initializer list - in this case - - @note When used without parentheses around an empty initializer list, @ref - basic_json() is called instead of this function, yielding the JSON null - value. - - @param[in] init initializer list with JSON values + @brief return whether type is primitive - @param[in] type_deduction internal parameter; when set to `true`, the type - of the JSON value is deducted from the initializer list @a init; when set - to `false`, the type provided via @a manual_type is forced. This mode is - used by the functions @ref array(std::initializer_list) and - @ref object(std::initializer_list). + This function returns true iff the JSON type is primitive (string, number, + boolean, or null). - @param[in] manual_type internal parameter; when @a type_deduction is set - to `false`, the created JSON value will use the provided type (only @ref - value_t::array and @ref value_t::object are valid); when @a type_deduction - is set to `true`, this parameter has no effect + @return `true` if type is primitive (string, number, boolean, or null), + `false` otherwise. - @throw std::domain_error if @a type_deduction is `false`, @a manual_type - is `value_t::object`, but @a init contains an element which is not a pair - whose first element is a string; example: `"cannot create object from - initializer list"` + @complexity Constant. - @complexity Linear in the size of the initializer list @a init. + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - @liveexample{The example below shows how JSON values are created from - initializer lists.,basic_json__list_init_t} + @liveexample{The following code exemplifies `is_primitive()` for all JSON + types.,is_primitive} - @sa @ref array(std::initializer_list) -- create a JSON array - value from an initializer list - @sa @ref object(std::initializer_list) -- create a JSON object - value from an initializer list + @sa @ref is_structured() -- returns whether JSON value is structured + @sa @ref is_null() -- returns whether JSON value is `null` + @sa @ref is_string() -- returns whether JSON value is a string + @sa @ref is_boolean() -- returns whether JSON value is a boolean + @sa @ref is_number() -- returns whether JSON value is a number @since version 1.0.0 */ - basic_json(std::initializer_list init, - bool type_deduction = true, - value_t manual_type = value_t::array) + constexpr bool is_primitive() const noexcept { - // check if each element is an array with two elements whose first - // element is a string - bool is_an_object = std::all_of(init.begin(), init.end(), - [](const basic_json & element) - { - return element.is_array() and element.size() == 2 and element[0].is_string(); - }); - - // adjust type if type deduction is not wanted - if (not type_deduction) - { - // if array is wanted, do not create an object though possible - if (manual_type == value_t::array) - { - is_an_object = false; - } - - // if object is wanted but impossible, throw an exception - if (manual_type == value_t::object and not is_an_object) - { - throw std::domain_error("cannot create object from initializer list"); - } - } - - if (is_an_object) - { - // the initializer list is a list of pairs -> create object - m_type = value_t::object; - m_value = value_t::object; - - std::for_each(init.begin(), init.end(), [this](const basic_json & element) - { - m_value.object->emplace(*(element[0].m_value.string), element[1]); - }); - } - else - { - // the initializer list describes an array -> create array - m_type = value_t::array; - m_value.array = create(init); - } - - assert_invariant(); + return is_null() or is_string() or is_boolean() or is_number(); } /*! - @brief explicitly create an array from an initializer list - - Creates a JSON array value from a given initializer list. That is, given a - list of values `a, b, c`, creates the JSON value `[a, b, c]`. If the - initializer list is empty, the empty array `[]` is created. + @brief return whether type is structured - @note This function is only needed to express two edge cases that cannot - be realized with the initializer list constructor (@ref - basic_json(std::initializer_list, bool, value_t)). These cases - are: - 1. creating an array whose elements are all pairs whose first element is a - string -- in this case, the initializer list constructor would create an - object, taking the first elements as keys - 2. creating an empty array -- passing the empty initializer list to the - initializer list constructor yields an empty object + This function returns true iff the JSON type is structured (array or + object). - @param[in] init initializer list with JSON values to create an array from - (optional) + @return `true` if type is structured (array or object), `false` otherwise. - @return JSON array value + @complexity Constant. - @complexity Linear in the size of @a init. + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - @liveexample{The following code shows an example for the `array` - function.,array} + @liveexample{The following code exemplifies `is_structured()` for all JSON + types.,is_structured} - @sa @ref basic_json(std::initializer_list, bool, value_t) -- - create a JSON value from an initializer list - @sa @ref object(std::initializer_list) -- create a JSON object - value from an initializer list + @sa @ref is_primitive() -- returns whether value is primitive + @sa @ref is_array() -- returns whether value is an array + @sa @ref is_object() -- returns whether value is an object @since version 1.0.0 */ - static basic_json array(std::initializer_list init = - std::initializer_list()) + constexpr bool is_structured() const noexcept { - return basic_json(init, false, value_t::array); + return is_array() or is_object(); } /*! - @brief explicitly create an object from an initializer list + @brief return whether value is null - Creates a JSON object value from a given initializer list. The initializer - lists elements must be pairs, and their first elements must be strings. If - the initializer list is empty, the empty object `{}` is created. + This function returns true iff the JSON value is null. - @note This function is only added for symmetry reasons. In contrast to the - related function @ref array(std::initializer_list), there are - no cases which can only be expressed by this function. That is, any - initializer list @a init can also be passed to the initializer list - constructor @ref basic_json(std::initializer_list, bool, - value_t). + @return `true` if type is null, `false` otherwise. - @param[in] init initializer list to create an object from (optional) + @complexity Constant. - @return JSON object value + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - @throw std::domain_error if @a init is not a pair whose first elements are - strings; thrown by - @ref basic_json(std::initializer_list, bool, value_t) + @liveexample{The following code exemplifies `is_null()` for all JSON + types.,is_null} - @complexity Linear in the size of @a init. + @since version 1.0.0 + */ + constexpr bool is_null() const noexcept + { + return m_type == value_t::null; + } - @liveexample{The following code shows an example for the `object` - function.,object} + /*! + @brief return whether value is a boolean - @sa @ref basic_json(std::initializer_list, bool, value_t) -- - create a JSON value from an initializer list - @sa @ref array(std::initializer_list) -- create a JSON array - value from an initializer list + This function returns true iff the JSON value is a boolean. + + @return `true` if type is boolean, `false` otherwise. + + @complexity Constant. + + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. + + @liveexample{The following code exemplifies `is_boolean()` for all JSON + types.,is_boolean} @since version 1.0.0 */ - static basic_json object(std::initializer_list init = - std::initializer_list()) + constexpr bool is_boolean() const noexcept { - return basic_json(init, false, value_t::object); + return m_type == value_t::boolean; } /*! - @brief construct an array with count copies of given value + @brief return whether value is a number - Constructs a JSON array value by creating @a cnt copies of a passed value. - In case @a cnt is `0`, an empty array is created. As postcondition, - `std::distance(begin(),end()) == cnt` holds. + This function returns true iff the JSON value is a number. This includes + both integer and floating-point values. - @param[in] cnt the number of JSON copies of @a val to create - @param[in] val the JSON value to copy + @return `true` if type is number (regardless whether integer, unsigned + integer or floating-type), `false` otherwise. - @complexity Linear in @a cnt. + @complexity Constant. - @liveexample{The following code shows examples for the @ref - basic_json(size_type\, const basic_json&) - constructor.,basic_json__size_type_basic_json} + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. + + @liveexample{The following code exemplifies `is_number()` for all JSON + types.,is_number} + + @sa @ref is_number_integer() -- check if value is an integer or unsigned + integer number + @sa @ref is_number_unsigned() -- check if value is an unsigned integer + number + @sa @ref is_number_float() -- check if value is a floating-point number @since version 1.0.0 */ - basic_json(size_type cnt, const basic_json& val) - : m_type(value_t::array) + constexpr bool is_number() const noexcept { - m_value.array = create(cnt, val); - assert_invariant(); + return is_number_integer() or is_number_float(); } /*! - @brief construct a JSON container given an iterator range - - Constructs the JSON value with the contents of the range `[first, last)`. - The semantics depends on the different types a JSON value can have: - - In case of primitive types (number, boolean, or string), @a first must - be `begin()` and @a last must be `end()`. In this case, the value is - copied. Otherwise, std::out_of_range is thrown. - - In case of structured types (array, object), the constructor behaves as - similar versions for `std::vector`. - - In case of a null type, std::domain_error is thrown. + @brief return whether value is an integer number - @tparam InputIT an input iterator type (@ref iterator or @ref - const_iterator) + This function returns true iff the JSON value is an integer or unsigned + integer number. This excludes floating-point values. - @param[in] first begin of the range to copy from (included) - @param[in] last end of the range to copy from (excluded) + @return `true` if type is an integer or unsigned integer number, `false` + otherwise. - @pre Iterators @a first and @a last must be initialized. **This - precondition is enforced with an assertion.** + @complexity Constant. - @throw std::domain_error if iterators are not compatible; that is, do not - belong to the same JSON value; example: `"iterators are not compatible"` - @throw std::out_of_range if iterators are for a primitive type (number, - boolean, or string) where an out of range error can be detected easily; - example: `"iterators out of range"` - @throw std::bad_alloc if allocation for object, array, or string fails - @throw std::domain_error if called with a null value; example: `"cannot - use construct with iterators from null"` + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - @complexity Linear in distance between @a first and @a last. + @liveexample{The following code exemplifies `is_number_integer()` for all + JSON types.,is_number_integer} - @liveexample{The example below shows several ways to create JSON values by - specifying a subrange with iterators.,basic_json__InputIt_InputIt} + @sa @ref is_number() -- check if value is a number + @sa @ref is_number_unsigned() -- check if value is an unsigned integer + number + @sa @ref is_number_float() -- check if value is a floating-point number @since version 1.0.0 */ - template::value or - std::is_same::value, int>::type = 0> - basic_json(InputIT first, InputIT last) + constexpr bool is_number_integer() const noexcept { - assert(first.m_object != nullptr); - assert(last.m_object != nullptr); + return m_type == value_t::number_integer or m_type == value_t::number_unsigned; + } - // make sure iterator fits the current value - if (first.m_object != last.m_object) - { - throw std::domain_error("iterators are not compatible"); - } + /*! + @brief return whether value is an unsigned integer number - // copy type from first iterator - m_type = first.m_object->m_type; + This function returns true iff the JSON value is an unsigned integer + number. This excludes floating-point and (signed) integer values. - // check if iterator range is complete for primitive values - switch (m_type) - { - case value_t::boolean: - case value_t::number_float: - case value_t::number_integer: - case value_t::number_unsigned: - case value_t::string: - { - if (not first.m_it.primitive_iterator.is_begin() or not last.m_it.primitive_iterator.is_end()) - { - throw std::out_of_range("iterators out of range"); - } - break; - } + @return `true` if type is an unsigned integer number, `false` otherwise. - default: - { - break; - } - } + @complexity Constant. - switch (m_type) - { - case value_t::number_integer: - { - m_value.number_integer = first.m_object->m_value.number_integer; - break; - } + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - case value_t::number_unsigned: - { - m_value.number_unsigned = first.m_object->m_value.number_unsigned; - break; - } + @liveexample{The following code exemplifies `is_number_unsigned()` for all + JSON types.,is_number_unsigned} - case value_t::number_float: - { - m_value.number_float = first.m_object->m_value.number_float; - break; - } + @sa @ref is_number() -- check if value is a number + @sa @ref is_number_integer() -- check if value is an integer or unsigned + integer number + @sa @ref is_number_float() -- check if value is a floating-point number - case value_t::boolean: - { - m_value.boolean = first.m_object->m_value.boolean; - break; - } + @since version 2.0.0 + */ + constexpr bool is_number_unsigned() const noexcept + { + return m_type == value_t::number_unsigned; + } - case value_t::string: - { - m_value = *first.m_object->m_value.string; - break; - } + /*! + @brief return whether value is a floating-point number - case value_t::object: - { - m_value.object = create(first.m_it.object_iterator, last.m_it.object_iterator); - break; - } + This function returns true iff the JSON value is a floating-point number. + This excludes integer and unsigned integer values. - case value_t::array: - { - m_value.array = create(first.m_it.array_iterator, last.m_it.array_iterator); - break; - } + @return `true` if type is a floating-point number, `false` otherwise. - default: - { - throw std::domain_error("cannot use construct with iterators from " + first.m_object->type_name()); - } - } + @complexity Constant. - assert_invariant(); + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. + + @liveexample{The following code exemplifies `is_number_float()` for all + JSON types.,is_number_float} + + @sa @ref is_number() -- check if value is number + @sa @ref is_number_integer() -- check if value is an integer number + @sa @ref is_number_unsigned() -- check if value is an unsigned integer + number + + @since version 1.0.0 + */ + constexpr bool is_number_float() const noexcept + { + return m_type == value_t::number_float; } /*! - @brief construct a JSON value given an input stream + @brief return whether value is an object - @param[in,out] i stream to read a serialized JSON value from - @param[in] cb a parser callback function of type @ref parser_callback_t - which is used to control the deserialization by filtering unwanted values - (optional) + This function returns true iff the JSON value is an object. - @complexity Linear in the length of the input. The parser is a predictive - LL(1) parser. The complexity can be higher if the parser callback function - @a cb has a super-linear complexity. + @return `true` if type is object, `false` otherwise. - @note A UTF-8 byte order mark is silently ignored. + @complexity Constant. - @deprecated This constructor is deprecated and will be removed in version - 3.0.0 to unify the interface of the library. Deserialization will be - done by stream operators or by calling one of the `parse` functions, - e.g. @ref parse(std::istream&, const parser_callback_t). That is, calls - like `json j(i);` for an input stream @a i need to be replaced by - `json j = json::parse(i);`. See the example below. + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - @liveexample{The example below demonstrates constructing a JSON value from - a `std::stringstream` with and without callback - function.,basic_json__istream} + @liveexample{The following code exemplifies `is_object()` for all JSON + types.,is_object} - @since version 2.0.0, deprecated in version 2.0.3, to be removed in - version 3.0.0 + @since version 1.0.0 */ - JSON_DEPRECATED - explicit basic_json(std::istream& i, const parser_callback_t cb = nullptr) + constexpr bool is_object() const noexcept { - *this = parser(i, cb).parse(); - assert_invariant(); + return m_type == value_t::object; } - /////////////////////////////////////// - // other constructors and destructor // - /////////////////////////////////////// - /*! - @brief copy constructor - - Creates a copy of a given JSON value. + @brief return whether value is an array - @param[in] other the JSON value to copy + This function returns true iff the JSON value is an array. - @complexity Linear in the size of @a other. + @return `true` if type is array, `false` otherwise. - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is linear. - - As postcondition, it holds: `other == basic_json(other)`. + @complexity Constant. - @throw std::bad_alloc if allocation for object, array, or string fails. + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - @liveexample{The following code shows an example for the copy - constructor.,basic_json__basic_json} + @liveexample{The following code exemplifies `is_array()` for all JSON + types.,is_array} @since version 1.0.0 */ - basic_json(const basic_json& other) - : m_type(other.m_type) + constexpr bool is_array() const noexcept { - // check of passed value is valid - other.assert_invariant(); - - switch (m_type) - { - case value_t::object: - { - m_value = *other.m_value.object; - break; - } - - case value_t::array: - { - m_value = *other.m_value.array; - break; - } + return m_type == value_t::array; + } - case value_t::string: - { - m_value = *other.m_value.string; - break; - } + /*! + @brief return whether value is a string - case value_t::boolean: - { - m_value = other.m_value.boolean; - break; - } + This function returns true iff the JSON value is a string. - case value_t::number_integer: - { - m_value = other.m_value.number_integer; - break; - } + @return `true` if type is string, `false` otherwise. - case value_t::number_unsigned: - { - m_value = other.m_value.number_unsigned; - break; - } + @complexity Constant. - case value_t::number_float: - { - m_value = other.m_value.number_float; - break; - } + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - default: - { - break; - } - } + @liveexample{The following code exemplifies `is_string()` for all JSON + types.,is_string} - assert_invariant(); + @since version 1.0.0 + */ + constexpr bool is_string() const noexcept + { + return m_type == value_t::string; } /*! - @brief move constructor + @brief return whether value is discarded - Move constructor. Constructs a JSON value with the contents of the given - value @a other using move semantics. It "steals" the resources from @a - other and leaves it as JSON null value. + This function returns true iff the JSON value was discarded during parsing + with a callback function (see @ref parser_callback_t). - @param[in,out] other value to move to this object + @note This function will always be `false` for JSON values after parsing. + That is, discarded values can only occur during parsing, but will be + removed when inside a structured value or replaced by null in other cases. - @post @a other is a JSON null value + @return `true` if type is discarded, `false` otherwise. @complexity Constant. - @liveexample{The code below shows the move constructor explicitly called - via std::move.,basic_json__moveconstructor} + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. + + @liveexample{The following code exemplifies `is_discarded()` for all JSON + types.,is_discarded} @since version 1.0.0 */ - basic_json(basic_json&& other) noexcept - : m_type(std::move(other.m_type)), - m_value(std::move(other.m_value)) + constexpr bool is_discarded() const noexcept { - // check that passed value is valid - other.assert_invariant(); - - // invalidate payload - other.m_type = value_t::null; - other.m_value = {}; - - assert_invariant(); + return m_type == value_t::discarded; } /*! - @brief copy assignment + @brief return the type of the JSON value (implicit) - Copy assignment operator. Copies a JSON value via the "copy and swap" - strategy: It is expressed in terms of the copy constructor, destructor, - and the swap() member function. + Implicitly return the type of the JSON value as a value from the @ref + value_t enumeration. - @param[in] other value to copy from + @return the type of the JSON value - @complexity Linear. + @complexity Constant. - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is linear. + @exceptionsafety No-throw guarantee: this member function never throws + exceptions. - @liveexample{The code below shows and example for the copy assignment. It - creates a copy of value `a` which is then swapped with `b`. Finally\, the - copy of `a` (which is the null value after the swap) is - destroyed.,basic_json__copyassignment} + @liveexample{The following code exemplifies the @ref value_t operator for + all JSON types.,operator__value_t} @since version 1.0.0 */ - reference& operator=(basic_json other) noexcept ( - std::is_nothrow_move_constructible::value and - std::is_nothrow_move_assignable::value and - std::is_nothrow_move_constructible::value and - std::is_nothrow_move_assignable::value - ) + constexpr operator value_t() const noexcept { - // check that passed value is valid - other.assert_invariant(); + return m_type; + } - using std::swap; - swap(m_type, other.m_type); - swap(m_value, other.m_value); + /// @} - assert_invariant(); - return *this; - } + private: + ////////////////// + // value access // + ////////////////// - /*! - @brief destructor + /// get a boolean (explicit) + boolean_t get_impl(boolean_t* /*unused*/) const + { + if (is_boolean()) + { + return m_value.boolean; + } - Destroys the JSON value and frees all allocated memory. + JSON_THROW(type_error::create(302, "type must be boolean, but is " + type_name())); + } - @complexity Linear. + /// get a pointer to the value (object) + object_t* get_impl_ptr(object_t* /*unused*/) noexcept + { + return is_object() ? m_value.object : nullptr; + } - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is linear. - - All stored elements are destroyed and all memory is freed. + /// get a pointer to the value (object) + constexpr const object_t* get_impl_ptr(const object_t* /*unused*/) const noexcept + { + return is_object() ? m_value.object : nullptr; + } - @since version 1.0.0 - */ - ~basic_json() + /// get a pointer to the value (array) + array_t* get_impl_ptr(array_t* /*unused*/) noexcept { - assert_invariant(); + return is_array() ? m_value.array : nullptr; + } - switch (m_type) - { - case value_t::object: - { - AllocatorType alloc; - alloc.destroy(m_value.object); - alloc.deallocate(m_value.object, 1); - break; - } + /// get a pointer to the value (array) + constexpr const array_t* get_impl_ptr(const array_t* /*unused*/) const noexcept + { + return is_array() ? m_value.array : nullptr; + } - case value_t::array: - { - AllocatorType alloc; - alloc.destroy(m_value.array); - alloc.deallocate(m_value.array, 1); - break; - } + /// get a pointer to the value (string) + string_t* get_impl_ptr(string_t* /*unused*/) noexcept + { + return is_string() ? m_value.string : nullptr; + } - case value_t::string: - { - AllocatorType alloc; - alloc.destroy(m_value.string); - alloc.deallocate(m_value.string, 1); - break; - } + /// get a pointer to the value (string) + constexpr const string_t* get_impl_ptr(const string_t* /*unused*/) const noexcept + { + return is_string() ? m_value.string : nullptr; + } - default: - { - // all other types need no specific destructor - break; - } - } + /// get a pointer to the value (boolean) + boolean_t* get_impl_ptr(boolean_t* /*unused*/) noexcept + { + return is_boolean() ? &m_value.boolean : nullptr; + } + + /// get a pointer to the value (boolean) + constexpr const boolean_t* get_impl_ptr(const boolean_t* /*unused*/) const noexcept + { + return is_boolean() ? &m_value.boolean : nullptr; } - /// @} - - public: - /////////////////////// - // object inspection // - /////////////////////// + /// get a pointer to the value (integer number) + number_integer_t* get_impl_ptr(number_integer_t* /*unused*/) noexcept + { + return is_number_integer() ? &m_value.number_integer : nullptr; + } - /// @name object inspection - /// Functions to inspect the type of a JSON value. - /// @{ + /// get a pointer to the value (integer number) + constexpr const number_integer_t* get_impl_ptr(const number_integer_t* /*unused*/) const noexcept + { + return is_number_integer() ? &m_value.number_integer : nullptr; + } - /*! - @brief serialization + /// get a pointer to the value (unsigned number) + number_unsigned_t* get_impl_ptr(number_unsigned_t* /*unused*/) noexcept + { + return is_number_unsigned() ? &m_value.number_unsigned : nullptr; + } - Serialization function for JSON values. The function tries to mimic - Python's `json.dumps()` function, and currently supports its @a indent - parameter. + /// get a pointer to the value (unsigned number) + constexpr const number_unsigned_t* get_impl_ptr(const number_unsigned_t* /*unused*/) const noexcept + { + return is_number_unsigned() ? &m_value.number_unsigned : nullptr; + } - @param[in] indent If indent is nonnegative, then array elements and object - members will be pretty-printed with that indent level. An indent level of - `0` will only insert newlines. `-1` (the default) selects the most compact - representation. + /// get a pointer to the value (floating-point number) + number_float_t* get_impl_ptr(number_float_t* /*unused*/) noexcept + { + return is_number_float() ? &m_value.number_float : nullptr; + } - @return string containing the serialization of the JSON value + /// get a pointer to the value (floating-point number) + constexpr const number_float_t* get_impl_ptr(const number_float_t* /*unused*/) const noexcept + { + return is_number_float() ? &m_value.number_float : nullptr; + } - @complexity Linear. + /*! + @brief helper function to implement get_ref() - @liveexample{The following example shows the effect of different @a indent - parameters to the result of the serialization.,dump} + This funcion helps to implement get_ref() without code duplication for + const and non-const overloads - @see https://docs.python.org/2/library/json.html#json.dump + @tparam ThisType will be deduced as `basic_json` or `const basic_json` - @since version 1.0.0 + @throw type_error.303 if ReferenceType does not match underlying value + type of the current JSON */ - string_t dump(const int indent = -1) const + template + static ReferenceType get_ref_impl(ThisType& obj) { - std::stringstream ss; - // fix locale problems - ss.imbue(std::locale::classic()); + // helper type + using PointerType = typename std::add_pointer::type; - // 6, 15 or 16 digits of precision allows round-trip IEEE 754 - // string->float->string, string->double->string or string->long - // double->string; to be safe, we read this value from - // std::numeric_limits::digits10 - ss.precision(std::numeric_limits::digits10); + // delegate the call to get_ptr<>() + auto ptr = obj.template get_ptr(); - if (indent >= 0) - { - dump(ss, true, static_cast(indent)); - } - else + if (ptr != nullptr) { - dump(ss, false, 0); + return *ptr; } - return ss.str(); + JSON_THROW(type_error::create(303, "incompatible ReferenceType for get_ref, actual type is " + obj.type_name())); } + public: + /// @name value access + /// Direct access to the stored value of a JSON value. + /// @{ + /*! - @brief return the type of the JSON value (explicit) + @brief get special-case overload - Return the type of the JSON value as a value from the @ref value_t - enumeration. + This overloads avoids a lot of template boilerplate, it can be seen as the + identity method - @return the type of the JSON value + @tparam BasicJsonType == @ref basic_json + + @return a copy of *this @complexity Constant. - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @since version 2.1.0 + */ + template < + typename BasicJsonType, + detail::enable_if_t::type, + basic_json_t>::value, + int> = 0 > + basic_json get() const + { + return *this; + } - @liveexample{The following code exemplifies `type()` for all JSON - types.,type} + /*! + @brief get a value (explicit) - @since version 1.0.0 + Explicit type conversion between the JSON value and a compatible value + which is [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible) + and [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible). + The value is converted by calling the @ref json_serializer + `from_json()` method. + + The function is equivalent to executing + @code {.cpp} + ValueType ret; + JSONSerializer::from_json(*this, ret); + return ret; + @endcode + + This overloads is chosen if: + - @a ValueType is not @ref basic_json, + - @ref json_serializer has a `from_json()` method of the form + `void from_json(const basic_json&, ValueType&)`, and + - @ref json_serializer does not have a `from_json()` method of + the form `ValueType from_json(const basic_json&)` + + @tparam ValueTypeCV the provided value type + @tparam ValueType the returned value type + + @return copy of the JSON value, converted to @a ValueType + + @throw what @ref json_serializer `from_json()` method throws + + @liveexample{The example below shows several conversions from JSON values + to other types. There a few things to note: (1) Floating-point numbers can + be converted to integers\, (2) A JSON array can be converted to a standard + `std::vector`\, (3) A JSON object can be converted to C++ + associative containers such as `std::unordered_map`.,get__ValueType_const} + + @since version 2.1.0 */ - constexpr value_t type() const noexcept + template < + typename ValueTypeCV, + typename ValueType = detail::uncvref_t, + detail::enable_if_t < + not std::is_same::value and + detail::has_from_json::value and + not detail::has_non_default_from_json::value, + int > = 0 > + ValueType get() const noexcept(noexcept( + JSONSerializer::from_json(std::declval(), std::declval()))) { - return m_type; + // we cannot static_assert on ValueTypeCV being non-const, because + // there is support for get(), which is why we + // still need the uncvref + static_assert(not std::is_reference::value, + "get() cannot be used with reference types, you might want to use get_ref()"); + static_assert(std::is_default_constructible::value, + "types must be DefaultConstructible when used with get()"); + + ValueType ret; + JSONSerializer::from_json(*this, ret); + return ret; } /*! - @brief return whether type is primitive + @brief get a value (explicit); special case - This function returns true iff the JSON type is primitive (string, number, - boolean, or null). + Explicit type conversion between the JSON value and a compatible value + which is **not** [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible) + and **not** [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible). + The value is converted by calling the @ref json_serializer + `from_json()` method. - @return `true` if type is primitive (string, number, boolean, or null), - `false` otherwise. + The function is equivalent to executing + @code {.cpp} + return JSONSerializer::from_json(*this); + @endcode - @complexity Constant. + This overloads is chosen if: + - @a ValueType is not @ref basic_json and + - @ref json_serializer has a `from_json()` method of the form + `ValueType from_json(const basic_json&)` - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @note If @ref json_serializer has both overloads of + `from_json()`, this one is chosen. - @liveexample{The following code exemplifies `is_primitive()` for all JSON - types.,is_primitive} + @tparam ValueTypeCV the provided value type + @tparam ValueType the returned value type - @sa @ref is_structured() -- returns whether JSON value is structured - @sa @ref is_null() -- returns whether JSON value is `null` - @sa @ref is_string() -- returns whether JSON value is a string - @sa @ref is_boolean() -- returns whether JSON value is a boolean - @sa @ref is_number() -- returns whether JSON value is a number + @return copy of the JSON value, converted to @a ValueType - @since version 1.0.0 + @throw what @ref json_serializer `from_json()` method throws + + @since version 2.1.0 */ - constexpr bool is_primitive() const noexcept + template < + typename ValueTypeCV, + typename ValueType = detail::uncvref_t, + detail::enable_if_t::value and + detail::has_non_default_from_json::value, int> = 0 > + ValueType get() const noexcept(noexcept( + JSONSerializer::from_json(std::declval()))) { - return is_null() or is_string() or is_boolean() or is_number(); + static_assert(not std::is_reference::value, + "get() cannot be used with reference types, you might want to use get_ref()"); + return JSONSerializer::from_json(*this); } /*! - @brief return whether type is structured + @brief get a pointer value (explicit) - This function returns true iff the JSON type is structured (array or - object). + Explicit pointer access to the internally stored JSON value. No copies are + made. - @return `true` if type is structured (array or object), `false` otherwise. + @warning The pointer becomes invalid if the underlying JSON object + changes. - @complexity Constant. + @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref + object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, + @ref number_unsigned_t, or @ref number_float_t. - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @return pointer to the internally stored JSON value if the requested + pointer type @a PointerType fits to the JSON value; `nullptr` otherwise - @liveexample{The following code exemplifies `is_structured()` for all JSON - types.,is_structured} + @complexity Constant. - @sa @ref is_primitive() -- returns whether value is primitive - @sa @ref is_array() -- returns whether value is an array - @sa @ref is_object() -- returns whether value is an object + @liveexample{The example below shows how pointers to internal values of a + JSON value can be requested. Note that no type conversions are made and a + `nullptr` is returned if the value and the requested pointer type does not + match.,get__PointerType} + + @sa @ref get_ptr() for explicit pointer-member access @since version 1.0.0 */ - constexpr bool is_structured() const noexcept + template::value, int>::type = 0> + PointerType get() noexcept { - return is_array() or is_object(); + // delegate the call to get_ptr + return get_ptr(); } /*! - @brief return whether value is null + @brief get a pointer value (explicit) + @copydoc get() + */ + template::value, int>::type = 0> + constexpr const PointerType get() const noexcept + { + // delegate the call to get_ptr + return get_ptr(); + } - This function returns true iff the JSON value is null. + /*! + @brief get a pointer value (implicit) - @return `true` if type is null, `false` otherwise. + Implicit pointer access to the internally stored JSON value. No copies are + made. - @complexity Constant. + @warning Writing data to the pointee of the result yields an undefined + state. - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref + object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, + @ref number_unsigned_t, or @ref number_float_t. Enforced by a static + assertion. - @liveexample{The following code exemplifies `is_null()` for all JSON - types.,is_null} + @return pointer to the internally stored JSON value if the requested + pointer type @a PointerType fits to the JSON value; `nullptr` otherwise + + @complexity Constant. + + @liveexample{The example below shows how pointers to internal values of a + JSON value can be requested. Note that no type conversions are made and a + `nullptr` is returned if the value and the requested pointer type does not + match.,get_ptr} @since version 1.0.0 */ - constexpr bool is_null() const noexcept + template::value, int>::type = 0> + PointerType get_ptr() noexcept { - return m_type == value_t::null; + // get the type of the PointerType (remove pointer and const) + using pointee_t = typename std::remove_const::type>::type>::type; + // make sure the type matches the allowed types + static_assert( + std::is_same::value + or std::is_same::value + or std::is_same::value + or std::is_same::value + or std::is_same::value + or std::is_same::value + or std::is_same::value + , "incompatible pointer type"); + + // delegate the call to get_impl_ptr<>() + return get_impl_ptr(static_cast(nullptr)); + } + + /*! + @brief get a pointer value (implicit) + @copydoc get_ptr() + */ + template::value and + std::is_const::type>::value, int>::type = 0> + constexpr const PointerType get_ptr() const noexcept + { + // get the type of the PointerType (remove pointer and const) + using pointee_t = typename std::remove_const::type>::type>::type; + // make sure the type matches the allowed types + static_assert( + std::is_same::value + or std::is_same::value + or std::is_same::value + or std::is_same::value + or std::is_same::value + or std::is_same::value + or std::is_same::value + , "incompatible pointer type"); + + // delegate the call to get_impl_ptr<>() const + return get_impl_ptr(static_cast(nullptr)); } - /*! - @brief return whether value is a boolean + /*! + @brief get a reference value (implicit) + + Implicit reference access to the internally stored JSON value. No copies + are made. + + @warning Writing data to the referee of the result yields an undefined + state. + + @tparam ReferenceType reference type; must be a reference to @ref array_t, + @ref object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, or + @ref number_float_t. Enforced by static assertion. - This function returns true iff the JSON value is a boolean. + @return reference to the internally stored JSON value if the requested + reference type @a ReferenceType fits to the JSON value; throws + type_error.303 otherwise - @return `true` if type is boolean, `false` otherwise. + @throw type_error.303 in case passed type @a ReferenceType is incompatible + with the stored JSON value; see example below @complexity Constant. - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @liveexample{The example shows several calls to `get_ref()`.,get_ref} - @liveexample{The following code exemplifies `is_boolean()` for all JSON - types.,is_boolean} + @since version 1.1.0 + */ + template::value, int>::type = 0> + ReferenceType get_ref() + { + // delegate call to get_ref_impl + return get_ref_impl(*this); + } - @since version 1.0.0 + /*! + @brief get a reference value (implicit) + @copydoc get_ref() */ - constexpr bool is_boolean() const noexcept + template::value and + std::is_const::type>::value, int>::type = 0> + ReferenceType get_ref() const { - return m_type == value_t::boolean; + // delegate call to get_ref_impl + return get_ref_impl(*this); } /*! - @brief return whether value is a number + @brief get a value (implicit) - This function returns true iff the JSON value is a number. This includes - both integer and floating-point values. + Implicit type conversion between the JSON value and a compatible value. + The call is realized by calling @ref get() const. - @return `true` if type is number (regardless whether integer, unsigned - integer or floating-type), `false` otherwise. + @tparam ValueType non-pointer type compatible to the JSON value, for + instance `int` for JSON integer numbers, `bool` for JSON booleans, or + `std::vector` types for JSON arrays. The character type of @ref string_t + as well as an initializer list of this type is excluded to avoid + ambiguities as these types implicitly convert to `std::string`. - @complexity Constant. + @return copy of the JSON value, converted to type @a ValueType - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @throw type_error.302 in case passed type @a ValueType is incompatible + to the JSON value type (e.g., the JSON value is of type boolean, but a + string is requested); see example below - @liveexample{The following code exemplifies `is_number()` for all JSON - types.,is_number} + @complexity Linear in the size of the JSON value. - @sa @ref is_number_integer() -- check if value is an integer or unsigned - integer number - @sa @ref is_number_unsigned() -- check if value is an unsigned integer - number - @sa @ref is_number_float() -- check if value is a floating-point number + @liveexample{The example below shows several conversions from JSON values + to other types. There a few things to note: (1) Floating-point numbers can + be converted to integers\, (2) A JSON array can be converted to a standard + `std::vector`\, (3) A JSON object can be converted to C++ + associative containers such as `std::unordered_map`.,operator__ValueType} @since version 1.0.0 */ - constexpr bool is_number() const noexcept + template < typename ValueType, typename std::enable_if < + not std::is_pointer::value and + not std::is_same::value +#ifndef _MSC_VER // fix for issue #167 operator<< ambiguity under VS2015 + and not std::is_same>::value +#endif +#if (defined(__cplusplus) && __cplusplus >= 201703L) || (defined(_MSC_VER) && _MSC_VER >1900 && defined(_HAS_CXX17) && _HAS_CXX17 == 1) // fix for issue #464 + and not std::is_same::value +#endif + , int >::type = 0 > + operator ValueType() const { - return is_number_integer() or is_number_float(); + // delegate the call to get<>() const + return get(); } - /*! - @brief return whether value is an integer number - - This function returns true iff the JSON value is an integer or unsigned - integer number. This excludes floating-point values. + /// @} - @return `true` if type is an integer or unsigned integer number, `false` - otherwise. - @complexity Constant. + //////////////////// + // element access // + //////////////////// - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + /// @name element access + /// Access to the JSON value. + /// @{ - @liveexample{The following code exemplifies `is_number_integer()` for all - JSON types.,is_number_integer} + /*! + @brief access specified array element with bounds checking - @sa @ref is_number() -- check if value is a number - @sa @ref is_number_unsigned() -- check if value is an unsigned integer - number - @sa @ref is_number_float() -- check if value is a floating-point number + Returns a reference to the element at specified location @a idx, with + bounds checking. - @since version 1.0.0 - */ - constexpr bool is_number_integer() const noexcept - { - return m_type == value_t::number_integer or m_type == value_t::number_unsigned; - } + @param[in] idx index of the element to access - /*! - @brief return whether value is an unsigned integer number + @return reference to the element at index @a idx - This function returns true iff the JSON value is an unsigned integer - number. This excludes floating-point and (signed) integer values. + @throw type_error.304 if the JSON value is not an array; in this case, + calling `at` with an index makes no sense. See example below. + @throw out_of_range.401 if the index @a idx is out of range of the array; + that is, `idx >= size()`. See example below. - @return `true` if type is an unsigned integer number, `false` otherwise. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. @complexity Constant. - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. - - @liveexample{The following code exemplifies `is_number_unsigned()` for all - JSON types.,is_number_unsigned} - - @sa @ref is_number() -- check if value is a number - @sa @ref is_number_integer() -- check if value is an integer or unsigned - integer number - @sa @ref is_number_float() -- check if value is a floating-point number + @since version 1.0.0 - @since version 2.0.0 + @liveexample{The example below shows how array elements can be read and + written using `at()`. It also demonstrates the different exceptions that + can be thrown.,at__size_type} */ - constexpr bool is_number_unsigned() const noexcept + reference at(size_type idx) { - return m_type == value_t::number_unsigned; + // at only works for arrays + if (is_array()) + { + JSON_TRY + { + return m_value.array->at(idx); + } + JSON_CATCH (std::out_of_range&) + { + // create better exception explanation + JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range")); + } + } + else + { + JSON_THROW(type_error::create(304, "cannot use at() with " + type_name())); + } } /*! - @brief return whether value is a floating-point number + @brief access specified array element with bounds checking - This function returns true iff the JSON value is a floating-point number. - This excludes integer and unsigned integer values. + Returns a const reference to the element at specified location @a idx, + with bounds checking. - @return `true` if type is a floating-point number, `false` otherwise. + @param[in] idx index of the element to access - @complexity Constant. + @return const reference to the element at index @a idx - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @throw type_error.304 if the JSON value is not an array; in this case, + calling `at` with an index makes no sense. See example below. + @throw out_of_range.401 if the index @a idx is out of range of the array; + that is, `idx >= size()`. See example below. - @liveexample{The following code exemplifies `is_number_float()` for all - JSON types.,is_number_float} + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. - @sa @ref is_number() -- check if value is number - @sa @ref is_number_integer() -- check if value is an integer number - @sa @ref is_number_unsigned() -- check if value is an unsigned integer - number + @complexity Constant. @since version 1.0.0 + + @liveexample{The example below shows how array elements can be read using + `at()`. It also demonstrates the different exceptions that can be thrown., + at__size_type_const} */ - constexpr bool is_number_float() const noexcept + const_reference at(size_type idx) const { - return m_type == value_t::number_float; + // at only works for arrays + if (is_array()) + { + JSON_TRY + { + return m_value.array->at(idx); + } + JSON_CATCH (std::out_of_range&) + { + // create better exception explanation + JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range")); + } + } + else + { + JSON_THROW(type_error::create(304, "cannot use at() with " + type_name())); + } } /*! - @brief return whether value is an object + @brief access specified object element with bounds checking - This function returns true iff the JSON value is an object. + Returns a reference to the element at with specified key @a key, with + bounds checking. - @return `true` if type is object, `false` otherwise. + @param[in] key key of the element to access - @complexity Constant. + @return reference to the element at key @a key - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @throw type_error.304 if the JSON value is not an object; in this case, + calling `at` with a key makes no sense. See example below. + @throw out_of_range.403 if the key @a key is is not stored in the object; + that is, `find(key) == end()`. See example below. - @liveexample{The following code exemplifies `is_object()` for all JSON - types.,is_object} + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. + + @complexity Logarithmic in the size of the container. + + @sa @ref operator[](const typename object_t::key_type&) for unchecked + access by reference + @sa @ref value() for access by value with a default value @since version 1.0.0 + + @liveexample{The example below shows how object elements can be read and + written using `at()`. It also demonstrates the different exceptions that + can be thrown.,at__object_t_key_type} */ - constexpr bool is_object() const noexcept + reference at(const typename object_t::key_type& key) { - return m_type == value_t::object; + // at only works for objects + if (is_object()) + { + JSON_TRY + { + return m_value.object->at(key); + } + JSON_CATCH (std::out_of_range&) + { + // create better exception explanation + JSON_THROW(out_of_range::create(403, "key '" + key + "' not found")); + } + } + else + { + JSON_THROW(type_error::create(304, "cannot use at() with " + type_name())); + } } /*! - @brief return whether value is an array + @brief access specified object element with bounds checking - This function returns true iff the JSON value is an array. + Returns a const reference to the element at with specified key @a key, + with bounds checking. - @return `true` if type is array, `false` otherwise. + @param[in] key key of the element to access - @complexity Constant. + @return const reference to the element at key @a key - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @throw type_error.304 if the JSON value is not an object; in this case, + calling `at` with a key makes no sense. See example below. + @throw out_of_range.403 if the key @a key is is not stored in the object; + that is, `find(key) == end()`. See example below. - @liveexample{The following code exemplifies `is_array()` for all JSON - types.,is_array} + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. + + @complexity Logarithmic in the size of the container. + + @sa @ref operator[](const typename object_t::key_type&) for unchecked + access by reference + @sa @ref value() for access by value with a default value @since version 1.0.0 + + @liveexample{The example below shows how object elements can be read using + `at()`. It also demonstrates the different exceptions that can be thrown., + at__object_t_key_type_const} */ - constexpr bool is_array() const noexcept + const_reference at(const typename object_t::key_type& key) const { - return m_type == value_t::array; + // at only works for objects + if (is_object()) + { + JSON_TRY + { + return m_value.object->at(key); + } + JSON_CATCH (std::out_of_range&) + { + // create better exception explanation + JSON_THROW(out_of_range::create(403, "key '" + key + "' not found")); + } + } + else + { + JSON_THROW(type_error::create(304, "cannot use at() with " + type_name())); + } } /*! - @brief return whether value is a string + @brief access specified array element - This function returns true iff the JSON value is a string. + Returns a reference to the element at specified location @a idx. - @return `true` if type is string, `false` otherwise. + @note If @a idx is beyond the range of the array (i.e., `idx >= size()`), + then the array is silently filled up with `null` values to make `idx` a + valid reference to the last stored element. - @complexity Constant. + @param[in] idx index of the element to access - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @return reference to the element at index @a idx - @liveexample{The following code exemplifies `is_string()` for all JSON - types.,is_string} + @throw type_error.305 if the JSON value is not an array or null; in that + cases, using the [] operator with an index makes no sense. + + @complexity Constant if @a idx is in the range of the array. Otherwise + linear in `idx - size()`. + + @liveexample{The example below shows how array elements can be read and + written using `[]` operator. Note the addition of `null` + values.,operatorarray__size_type} @since version 1.0.0 */ - constexpr bool is_string() const noexcept + reference operator[](size_type idx) { - return m_type == value_t::string; + // implicitly convert null value to an empty array + if (is_null()) + { + m_type = value_t::array; + m_value.array = create(); + assert_invariant(); + } + + // operator[] only works for arrays + if (is_array()) + { + // fill up array with null values if given idx is outside range + if (idx >= m_value.array->size()) + { + m_value.array->insert(m_value.array->end(), + idx - m_value.array->size() + 1, + basic_json()); + } + + return m_value.array->operator[](idx); + } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + type_name())); } /*! - @brief return whether value is discarded + @brief access specified array element - This function returns true iff the JSON value was discarded during parsing - with a callback function (see @ref parser_callback_t). + Returns a const reference to the element at specified location @a idx. - @note This function will always be `false` for JSON values after parsing. - That is, discarded values can only occur during parsing, but will be - removed when inside a structured value or replaced by null in other cases. + @param[in] idx index of the element to access - @return `true` if type is discarded, `false` otherwise. + @return const reference to the element at index @a idx - @complexity Constant. + @throw type_error.305 if the JSON value is not an array; in that cases, + using the [] operator with an index makes no sense. - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @complexity Constant. - @liveexample{The following code exemplifies `is_discarded()` for all JSON - types.,is_discarded} + @liveexample{The example below shows how array elements can be read using + the `[]` operator.,operatorarray__size_type_const} @since version 1.0.0 */ - constexpr bool is_discarded() const noexcept + const_reference operator[](size_type idx) const { - return m_type == value_t::discarded; + // const operator[] only works for arrays + if (is_array()) + { + return m_value.array->operator[](idx); + } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + type_name())); } /*! - @brief return the type of the JSON value (implicit) + @brief access specified object element - Implicitly return the type of the JSON value as a value from the @ref - value_t enumeration. + Returns a reference to the element at with specified key @a key. - @return the type of the JSON value + @note If @a key is not found in the object, then it is silently added to + the object and filled with a `null` value to make `key` a valid reference. + In case the value was `null` before, it is converted to an object. - @complexity Constant. + @param[in] key key of the element to access - @exceptionsafety No-throw guarantee: this member function never throws - exceptions. + @return reference to the element at key @a key - @liveexample{The following code exemplifies the @ref value_t operator for - all JSON types.,operator__value_t} + @throw type_error.305 if the JSON value is not an object or null; in that + cases, using the [] operator with a key makes no sense. - @since version 1.0.0 - */ - constexpr operator value_t() const noexcept - { - return m_type; - } + @complexity Logarithmic in the size of the container. - /// @} + @liveexample{The example below shows how object elements can be read and + written using the `[]` operator.,operatorarray__key_type} - private: - ////////////////// - // value access // - ////////////////// + @sa @ref at(const typename object_t::key_type&) for access by reference + with range checking + @sa @ref value() for access by value with a default value - /// get an object (explicit) - template::value and - std::is_convertible::value, int>::type = 0> - T get_impl(T*) const + @since version 1.0.0 + */ + reference operator[](const typename object_t::key_type& key) { - if (is_object()) - { - return T(m_value.object->begin(), m_value.object->end()); - } - else + // implicitly convert null value to an empty object + if (is_null()) { - throw std::domain_error("type must be object, but is " + type_name()); + m_type = value_t::object; + m_value.object = create(); + assert_invariant(); } - } - /// get an object (explicit) - object_t get_impl(object_t*) const - { + // operator[] only works for objects if (is_object()) { - return *(m_value.object); - } - else - { - throw std::domain_error("type must be object, but is " + type_name()); + return m_value.object->operator[](key); } - } - /// get an array (explicit) - template::value and - not std::is_same::value and - not std::is_arithmetic::value and - not std::is_convertible::value and - not has_mapped_type::value, int>::type = 0> - T get_impl(T*) const - { - if (is_array()) - { - T to_vector; - std::transform(m_value.array->begin(), m_value.array->end(), - std::inserter(to_vector, to_vector.end()), [](basic_json i) - { - return i.get(); - }); - return to_vector; - } - else - { - throw std::domain_error("type must be array, but is " + type_name()); - } + JSON_THROW(type_error::create(305, "cannot use operator[] with " + type_name())); } - /// get an array (explicit) - template::value and - not std::is_same::value, int>::type = 0> - std::vector get_impl(std::vector*) const - { - if (is_array()) - { - std::vector to_vector; - to_vector.reserve(m_value.array->size()); - std::transform(m_value.array->begin(), m_value.array->end(), - std::inserter(to_vector, to_vector.end()), [](basic_json i) - { - return i.get(); - }); - return to_vector; - } - else - { - throw std::domain_error("type must be array, but is " + type_name()); - } - } + /*! + @brief read-only access specified object element - /// get an array (explicit) - template::value and - not has_mapped_type::value, int>::type = 0> - T get_impl(T*) const - { - if (is_array()) - { - return T(m_value.array->begin(), m_value.array->end()); - } - else - { - throw std::domain_error("type must be array, but is " + type_name()); - } - } + Returns a const reference to the element at with specified key @a key. No + bounds checking is performed. - /// get an array (explicit) - array_t get_impl(array_t*) const - { - if (is_array()) - { - return *(m_value.array); - } - else - { - throw std::domain_error("type must be array, but is " + type_name()); - } - } + @warning If the element with key @a key does not exist, the behavior is + undefined. + + @param[in] key key of the element to access + + @return const reference to the element at key @a key - /// get a string (explicit) - template::value, int>::type = 0> - T get_impl(T*) const + @pre The element with key @a key must exist. **This precondition is + enforced with an assertion.** + + @throw type_error.305 if the JSON value is not an object; in that cases, + using the [] operator with a key makes no sense. + + @complexity Logarithmic in the size of the container. + + @liveexample{The example below shows how object elements can be read using + the `[]` operator.,operatorarray__key_type_const} + + @sa @ref at(const typename object_t::key_type&) for access by reference + with range checking + @sa @ref value() for access by value with a default value + + @since version 1.0.0 + */ + const_reference operator[](const typename object_t::key_type& key) const { - if (is_string()) - { - return *m_value.string; - } - else + // const operator[] only works for objects + if (is_object()) { - throw std::domain_error("type must be string, but is " + type_name()); + assert(m_value.object->find(key) != m_value.object->end()); + return m_value.object->find(key)->second; } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + type_name())); } - /// get a number (explicit) - template::value, int>::type = 0> - T get_impl(T*) const - { - switch (m_type) - { - case value_t::number_integer: - { - return static_cast(m_value.number_integer); - } + /*! + @brief access specified object element - case value_t::number_unsigned: - { - return static_cast(m_value.number_unsigned); - } + Returns a reference to the element at with specified key @a key. - case value_t::number_float: - { - return static_cast(m_value.number_float); - } + @note If @a key is not found in the object, then it is silently added to + the object and filled with a `null` value to make `key` a valid reference. + In case the value was `null` before, it is converted to an object. - default: - { - throw std::domain_error("type must be number, but is " + type_name()); - } - } - } + @param[in] key key of the element to access - /// get a boolean (explicit) - constexpr boolean_t get_impl(boolean_t*) const - { - return is_boolean() - ? m_value.boolean - : throw std::domain_error("type must be boolean, but is " + type_name()); - } + @return reference to the element at key @a key - /// get a pointer to the value (object) - object_t* get_impl_ptr(object_t*) noexcept - { - return is_object() ? m_value.object : nullptr; - } + @throw type_error.305 if the JSON value is not an object or null; in that + cases, using the [] operator with a key makes no sense. - /// get a pointer to the value (object) - constexpr const object_t* get_impl_ptr(const object_t*) const noexcept - { - return is_object() ? m_value.object : nullptr; - } + @complexity Logarithmic in the size of the container. - /// get a pointer to the value (array) - array_t* get_impl_ptr(array_t*) noexcept - { - return is_array() ? m_value.array : nullptr; - } + @liveexample{The example below shows how object elements can be read and + written using the `[]` operator.,operatorarray__key_type} - /// get a pointer to the value (array) - constexpr const array_t* get_impl_ptr(const array_t*) const noexcept - { - return is_array() ? m_value.array : nullptr; - } + @sa @ref at(const typename object_t::key_type&) for access by reference + with range checking + @sa @ref value() for access by value with a default value - /// get a pointer to the value (string) - string_t* get_impl_ptr(string_t*) noexcept + @since version 1.0.0 + */ + template + reference operator[](T * (&key)[n]) { - return is_string() ? m_value.string : nullptr; + return operator[](static_cast(key)); } - /// get a pointer to the value (string) - constexpr const string_t* get_impl_ptr(const string_t*) const noexcept - { - return is_string() ? m_value.string : nullptr; - } + /*! + @brief read-only access specified object element - /// get a pointer to the value (boolean) - boolean_t* get_impl_ptr(boolean_t*) noexcept - { - return is_boolean() ? &m_value.boolean : nullptr; - } + Returns a const reference to the element at with specified key @a key. No + bounds checking is performed. - /// get a pointer to the value (boolean) - constexpr const boolean_t* get_impl_ptr(const boolean_t*) const noexcept - { - return is_boolean() ? &m_value.boolean : nullptr; - } + @warning If the element with key @a key does not exist, the behavior is + undefined. - /// get a pointer to the value (integer number) - number_integer_t* get_impl_ptr(number_integer_t*) noexcept - { - return is_number_integer() ? &m_value.number_integer : nullptr; - } + @note This function is required for compatibility reasons with Clang. - /// get a pointer to the value (integer number) - constexpr const number_integer_t* get_impl_ptr(const number_integer_t*) const noexcept - { - return is_number_integer() ? &m_value.number_integer : nullptr; - } + @param[in] key key of the element to access - /// get a pointer to the value (unsigned number) - number_unsigned_t* get_impl_ptr(number_unsigned_t*) noexcept - { - return is_number_unsigned() ? &m_value.number_unsigned : nullptr; - } + @return const reference to the element at key @a key - /// get a pointer to the value (unsigned number) - constexpr const number_unsigned_t* get_impl_ptr(const number_unsigned_t*) const noexcept - { - return is_number_unsigned() ? &m_value.number_unsigned : nullptr; - } + @throw type_error.305 if the JSON value is not an object; in that cases, + using the [] operator with a key makes no sense. - /// get a pointer to the value (floating-point number) - number_float_t* get_impl_ptr(number_float_t*) noexcept - { - return is_number_float() ? &m_value.number_float : nullptr; - } + @complexity Logarithmic in the size of the container. - /// get a pointer to the value (floating-point number) - constexpr const number_float_t* get_impl_ptr(const number_float_t*) const noexcept + @liveexample{The example below shows how object elements can be read using + the `[]` operator.,operatorarray__key_type_const} + + @sa @ref at(const typename object_t::key_type&) for access by reference + with range checking + @sa @ref value() for access by value with a default value + + @since version 1.0.0 + */ + template + const_reference operator[](T * (&key)[n]) const { - return is_number_float() ? &m_value.number_float : nullptr; + return operator[](static_cast(key)); } /*! - @brief helper function to implement get_ref() + @brief access specified object element - This funcion helps to implement get_ref() without code duplication for - const and non-const overloads + Returns a reference to the element at with specified key @a key. - @tparam ThisType will be deduced as `basic_json` or `const basic_json` + @note If @a key is not found in the object, then it is silently added to + the object and filled with a `null` value to make `key` a valid reference. + In case the value was `null` before, it is converted to an object. - @throw std::domain_error if ReferenceType does not match underlying value - type of the current JSON - */ - template - static ReferenceType get_ref_impl(ThisType& obj) - { - // helper type - using PointerType = typename std::add_pointer::type; + @param[in] key key of the element to access - // delegate the call to get_ptr<>() - auto ptr = obj.template get_ptr(); + @return reference to the element at key @a key - if (ptr != nullptr) + @throw type_error.305 if the JSON value is not an object or null; in that + cases, using the [] operator with a key makes no sense. + + @complexity Logarithmic in the size of the container. + + @liveexample{The example below shows how object elements can be read and + written using the `[]` operator.,operatorarray__key_type} + + @sa @ref at(const typename object_t::key_type&) for access by reference + with range checking + @sa @ref value() for access by value with a default value + + @since version 1.1.0 + */ + template + reference operator[](T* key) + { + // implicitly convert null to object + if (is_null()) { - return *ptr; + m_type = value_t::object; + m_value = value_t::object; + assert_invariant(); } - else + + // at only works for objects + if (is_object()) { - throw std::domain_error("incompatible ReferenceType for get_ref, actual type is " + - obj.type_name()); + return m_value.object->operator[](key); } - } - - public: - /// @name value access - /// Direct access to the stored value of a JSON value. - /// @{ + JSON_THROW(type_error::create(305, "cannot use operator[] with " + type_name())); + } /*! - @brief get a value (explicit) + @brief read-only access specified object element - Explicit type conversion between the JSON value and a compatible value. + Returns a const reference to the element at with specified key @a key. No + bounds checking is performed. - @tparam ValueType non-pointer type compatible to the JSON value, for - instance `int` for JSON integer numbers, `bool` for JSON booleans, or - `std::vector` types for JSON arrays + @warning If the element with key @a key does not exist, the behavior is + undefined. - @return copy of the JSON value, converted to type @a ValueType + @param[in] key key of the element to access - @throw std::domain_error in case passed type @a ValueType is incompatible - to JSON; example: `"type must be object, but is null"` + @return const reference to the element at key @a key - @complexity Linear in the size of the JSON value. + @pre The element with key @a key must exist. **This precondition is + enforced with an assertion.** - @liveexample{The example below shows several conversions from JSON values - to other types. There a few things to note: (1) Floating-point numbers can - be converted to integers\, (2) A JSON array can be converted to a standard - `std::vector`\, (3) A JSON object can be converted to C++ - associative containers such as `std::unordered_map`.,get__ValueType_const} + @throw type_error.305 if the JSON value is not an object; in that cases, + using the [] operator with a key makes no sense. - @internal - The idea of using a casted null pointer to choose the correct - implementation is from . - @endinternal + @complexity Logarithmic in the size of the container. - @sa @ref operator ValueType() const for implicit conversion - @sa @ref get() for pointer-member access + @liveexample{The example below shows how object elements can be read using + the `[]` operator.,operatorarray__key_type_const} - @since version 1.0.0 + @sa @ref at(const typename object_t::key_type&) for access by reference + with range checking + @sa @ref value() for access by value with a default value + + @since version 1.1.0 */ - template::value, int>::type = 0> - ValueType get() const + template + const_reference operator[](T* key) const { - return get_impl(static_cast(nullptr)); + // at only works for objects + if (is_object()) + { + assert(m_value.object->find(key) != m_value.object->end()); + return m_value.object->find(key)->second; + } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + type_name())); } /*! - @brief get a pointer value (explicit) + @brief access specified object element with default value - Explicit pointer access to the internally stored JSON value. No copies are - made. + Returns either a copy of an object's element at the specified key @a key + or a given default value if no element with key @a key exists. - @warning The pointer becomes invalid if the underlying JSON object - changes. + The function is basically equivalent to executing + @code {.cpp} + try { + return at(key); + } catch(out_of_range) { + return default_value; + } + @endcode - @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref - object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, - @ref number_unsigned_t, or @ref number_float_t. + @note Unlike @ref at(const typename object_t::key_type&), this function + does not throw if the given key @a key was not found. - @return pointer to the internally stored JSON value if the requested - pointer type @a PointerType fits to the JSON value; `nullptr` otherwise + @note Unlike @ref operator[](const typename object_t::key_type& key), this + function does not implicitly add an element to the position defined by @a + key. This function is furthermore also applicable to const objects. - @complexity Constant. + @param[in] key key of the element to access + @param[in] default_value the value to return if @a key is not found - @liveexample{The example below shows how pointers to internal values of a - JSON value can be requested. Note that no type conversions are made and a - `nullptr` is returned if the value and the requested pointer type does not - match.,get__PointerType} + @tparam ValueType type compatible to JSON values, for instance `int` for + JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for + JSON arrays. Note the type of the expected value at @a key and the default + value @a default_value must be compatible. - @sa @ref get_ptr() for explicit pointer-member access + @return copy of the element at key @a key or @a default_value if @a key + is not found + + @throw type_error.306 if the JSON value is not an objec; in that cases, + using `value()` with a key makes no sense. + + @complexity Logarithmic in the size of the container. + + @liveexample{The example below shows how object elements can be queried + with a default value.,basic_json__value} + + @sa @ref at(const typename object_t::key_type&) for access by reference + with range checking + @sa @ref operator[](const typename object_t::key_type&) for unchecked + access by reference @since version 1.0.0 */ - template::value, int>::type = 0> - PointerType get() noexcept + template::value, int>::type = 0> + ValueType value(const typename object_t::key_type& key, ValueType default_value) const { - // delegate the call to get_ptr - return get_ptr(); + // at only works for objects + if (is_object()) + { + // if key is found, return value and given default value otherwise + const auto it = find(key); + if (it != end()) + { + return *it; + } + + return default_value; + } + else + { + JSON_THROW(type_error::create(306, "cannot use value() with " + type_name())); + } } /*! - @brief get a pointer value (explicit) - @copydoc get() + @brief overload for a default value of type const char* + @copydoc basic_json::value(const typename object_t::key_type&, ValueType) const */ - template::value, int>::type = 0> - constexpr const PointerType get() const noexcept + string_t value(const typename object_t::key_type& key, const char* default_value) const { - // delegate the call to get_ptr - return get_ptr(); + return value(key, string_t(default_value)); } /*! - @brief get a pointer value (implicit) + @brief access specified object element via JSON Pointer with default value - Implicit pointer access to the internally stored JSON value. No copies are - made. + Returns either a copy of an object's element at the specified key @a key + or a given default value if no element with key @a key exists. + + The function is basically equivalent to executing + @code {.cpp} + try { + return at(ptr); + } catch(out_of_range) { + return default_value; + } + @endcode + + @note Unlike @ref at(const json_pointer&), this function does not throw + if the given key @a key was not found. + + @param[in] ptr a JSON pointer to the element to access + @param[in] default_value the value to return if @a ptr found no value + + @tparam ValueType type compatible to JSON values, for instance `int` for + JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for + JSON arrays. Note the type of the expected value at @a key and the default + value @a default_value must be compatible. - @warning Writing data to the pointee of the result yields an undefined - state. + @return copy of the element at key @a key or @a default_value if @a key + is not found - @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref - object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, - @ref number_unsigned_t, or @ref number_float_t. Enforced by a static - assertion. + @throw type_error.306 if the JSON value is not an objec; in that cases, + using `value()` with a key makes no sense. - @return pointer to the internally stored JSON value if the requested - pointer type @a PointerType fits to the JSON value; `nullptr` otherwise + @complexity Logarithmic in the size of the container. - @complexity Constant. + @liveexample{The example below shows how object elements can be queried + with a default value.,basic_json__value_ptr} - @liveexample{The example below shows how pointers to internal values of a - JSON value can be requested. Note that no type conversions are made and a - `nullptr` is returned if the value and the requested pointer type does not - match.,get_ptr} + @sa @ref operator[](const json_pointer&) for unchecked access by reference - @since version 1.0.0 + @since version 2.0.2 */ - template::value, int>::type = 0> - PointerType get_ptr() noexcept + template::value, int>::type = 0> + ValueType value(const json_pointer& ptr, ValueType default_value) const { - // get the type of the PointerType (remove pointer and const) - using pointee_t = typename std::remove_const::type>::type>::type; - // make sure the type matches the allowed types - static_assert( - std::is_same::value - or std::is_same::value - or std::is_same::value - or std::is_same::value - or std::is_same::value - or std::is_same::value - or std::is_same::value - , "incompatible pointer type"); + // at only works for objects + if (is_object()) + { + // if pointer resolves a value, return it or use default value + JSON_TRY + { + return ptr.get_checked(this); + } + JSON_CATCH (out_of_range&) + { + return default_value; + } + } - // delegate the call to get_impl_ptr<>() - return get_impl_ptr(static_cast(nullptr)); + JSON_THROW(type_error::create(306, "cannot use value() with " + type_name())); } /*! - @brief get a pointer value (implicit) - @copydoc get_ptr() + @brief overload for a default value of type const char* + @copydoc basic_json::value(const json_pointer&, ValueType) const */ - template::value and - std::is_const::type>::value, int>::type = 0> - constexpr const PointerType get_ptr() const noexcept + string_t value(const json_pointer& ptr, const char* default_value) const { - // get the type of the PointerType (remove pointer and const) - using pointee_t = typename std::remove_const::type>::type>::type; - // make sure the type matches the allowed types - static_assert( - std::is_same::value - or std::is_same::value - or std::is_same::value - or std::is_same::value - or std::is_same::value - or std::is_same::value - or std::is_same::value - , "incompatible pointer type"); - - // delegate the call to get_impl_ptr<>() const - return get_impl_ptr(static_cast(nullptr)); + return value(ptr, string_t(default_value)); } /*! - @brief get a reference value (implicit) + @brief access the first element - Implict reference access to the internally stored JSON value. No copies - are made. + Returns a reference to the first element in the container. For a JSON + container `c`, the expression `c.front()` is equivalent to `*c.begin()`. - @warning Writing data to the referee of the result yields an undefined - state. + @return In case of a structured type (array or object), a reference to the + first element is returned. In case of number, string, or boolean values, a + reference to the value is returned. - @tparam ReferenceType reference type; must be a reference to @ref array_t, - @ref object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, or - @ref number_float_t. Enforced by static assertion. + @complexity Constant. - @return reference to the internally stored JSON value if the requested - reference type @a ReferenceType fits to the JSON value; throws - std::domain_error otherwise + @pre The JSON value must not be `null` (would throw `std::out_of_range`) + or an empty array or object (undefined behavior, **guarded by + assertions**). + @post The JSON value remains unchanged. - @throw std::domain_error in case passed type @a ReferenceType is - incompatible with the stored JSON value + @throw invalid_iterator.214 when called on `null` value - @complexity Constant. + @liveexample{The following code shows an example for `front()`.,front} - @liveexample{The example shows several calls to `get_ref()`.,get_ref} + @sa @ref back() -- access the last element - @since version 1.1.0 + @since version 1.0.0 */ - template::value, int>::type = 0> - ReferenceType get_ref() + reference front() { - // delegate call to get_ref_impl - return get_ref_impl(*this); + return *begin(); } /*! - @brief get a reference value (implicit) - @copydoc get_ref() + @copydoc basic_json::front() */ - template::value and - std::is_const::type>::value, int>::type = 0> - ReferenceType get_ref() const + const_reference front() const { - // delegate call to get_ref_impl - return get_ref_impl(*this); + return *cbegin(); } /*! - @brief get a value (implicit) + @brief access the last element - Implicit type conversion between the JSON value and a compatible value. - The call is realized by calling @ref get() const. + Returns a reference to the last element in the container. For a JSON + container `c`, the expression `c.back()` is equivalent to + @code {.cpp} + auto tmp = c.end(); + --tmp; + return *tmp; + @endcode - @tparam ValueType non-pointer type compatible to the JSON value, for - instance `int` for JSON integer numbers, `bool` for JSON booleans, or - `std::vector` types for JSON arrays. The character type of @ref string_t - as well as an initializer list of this type is excluded to avoid - ambiguities as these types implicitly convert to `std::string`. + @return In case of a structured type (array or object), a reference to the + last element is returned. In case of number, string, or boolean values, a + reference to the value is returned. - @return copy of the JSON value, converted to type @a ValueType + @complexity Constant. - @throw std::domain_error in case passed type @a ValueType is incompatible - to JSON, thrown by @ref get() const + @pre The JSON value must not be `null` (would throw `std::out_of_range`) + or an empty array or object (undefined behavior, **guarded by + assertions**). + @post The JSON value remains unchanged. - @complexity Linear in the size of the JSON value. + @throw invalid_iterator.214 when called on a `null` value. See example + below. - @liveexample{The example below shows several conversions from JSON values - to other types. There a few things to note: (1) Floating-point numbers can - be converted to integers\, (2) A JSON array can be converted to a standard - `std::vector`\, (3) A JSON object can be converted to C++ - associative containers such as `std::unordered_map`.,operator__ValueType} + @liveexample{The following code shows an example for `back()`.,back} + + @sa @ref front() -- access the first element @since version 1.0.0 */ - template < typename ValueType, typename std::enable_if < - not std::is_pointer::value and - not std::is_same::value -#ifndef _MSC_VER // Fix for issue #167 operator<< abiguity under VS2015 - and not std::is_same>::value -#endif - , int >::type = 0 > - operator ValueType() const + reference back() { - // delegate the call to get<>() const - return get(); + auto tmp = end(); + --tmp; + return *tmp; } - /// @} + /*! + @copydoc basic_json::back() + */ + const_reference back() const + { + auto tmp = cend(); + --tmp; + return *tmp; + } + /*! + @brief remove element given an iterator - //////////////////// - // element access // - //////////////////// + Removes the element specified by iterator @a pos. The iterator @a pos must + be valid and dereferenceable. Thus the `end()` iterator (which is valid, + but is not dereferenceable) cannot be used as a value for @a pos. - /// @name element access - /// Access to the JSON value. - /// @{ + If called on a primitive type other than `null`, the resulting JSON value + will be `null`. - /*! - @brief access specified array element with bounds checking + @param[in] pos iterator to the element to remove + @return Iterator following the last removed element. If the iterator @a + pos refers to the last element, the `end()` iterator is returned. - Returns a reference to the element at specified location @a idx, with - bounds checking. + @tparam IteratorType an @ref iterator or @ref const_iterator - @param[in] idx index of the element to access + @post Invalidates iterators and references at or after the point of the + erase, including the `end()` iterator. - @return reference to the element at index @a idx + @throw type_error.307 if called on a `null` value; example: `"cannot use + erase() with null"` + @throw invalid_iterator.202 if called on an iterator which does not belong + to the current JSON value; example: `"iterator does not fit current + value"` + @throw invalid_iterator.205 if called on a primitive type with invalid + iterator (i.e., any iterator which is not `begin()`); example: `"iterator + out of range"` - @throw std::domain_error if the JSON value is not an array; example: - `"cannot use at() with string"` - @throw std::out_of_range if the index @a idx is out of range of the array; - that is, `idx >= size()`; example: `"array index 7 is out of range"` + @complexity The complexity depends on the type: + - objects: amortized constant + - arrays: linear in distance between @a pos and the end of the container + - strings: linear in the length of the string + - other types: constant - @complexity Constant. + @liveexample{The example shows the result of `erase()` for different JSON + types.,erase__IteratorType} - @liveexample{The example below shows how array elements can be read and - written using `at()`.,at__size_type} + @sa @ref erase(IteratorType, IteratorType) -- removes the elements in + the given range + @sa @ref erase(const typename object_t::key_type&) -- removes the element + from an object at the given key + @sa @ref erase(const size_type) -- removes the element from an array at + the given index @since version 1.0.0 */ - reference at(size_type idx) + template::value or + std::is_same::value, int>::type + = 0> + IteratorType erase(IteratorType pos) { - // at only works for arrays - if (is_array()) - { - try - { - return m_value.array->at(idx); - } - catch (std::out_of_range&) - { - // create better exception explanation - throw std::out_of_range("array index " + std::to_string(idx) + " is out of range"); - } - } - else + // make sure iterator fits the current value + if (this != pos.m_object) { - throw std::domain_error("cannot use at() with " + type_name()); + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); } - } - - /*! - @brief access specified array element with bounds checking - - Returns a const reference to the element at specified location @a idx, - with bounds checking. - @param[in] idx index of the element to access + IteratorType result = end(); - @return const reference to the element at index @a idx + switch (m_type) + { + case value_t::boolean: + case value_t::number_float: + case value_t::number_integer: + case value_t::number_unsigned: + case value_t::string: + { + if (not pos.m_it.primitive_iterator.is_begin()) + { + JSON_THROW(invalid_iterator::create(205, "iterator out of range")); + } - @throw std::domain_error if the JSON value is not an array; example: - `"cannot use at() with string"` - @throw std::out_of_range if the index @a idx is out of range of the array; - that is, `idx >= size()`; example: `"array index 7 is out of range"` + if (is_string()) + { + AllocatorType alloc; + alloc.destroy(m_value.string); + alloc.deallocate(m_value.string, 1); + m_value.string = nullptr; + } - @complexity Constant. + m_type = value_t::null; + assert_invariant(); + break; + } - @liveexample{The example below shows how array elements can be read using - `at()`.,at__size_type_const} + case value_t::object: + { + result.m_it.object_iterator = m_value.object->erase(pos.m_it.object_iterator); + break; + } - @since version 1.0.0 - */ - const_reference at(size_type idx) const - { - // at only works for arrays - if (is_array()) - { - try + case value_t::array: { - return m_value.array->at(idx); + result.m_it.array_iterator = m_value.array->erase(pos.m_it.array_iterator); + break; } - catch (std::out_of_range&) + + default: { - // create better exception explanation - throw std::out_of_range("array index " + std::to_string(idx) + " is out of range"); + JSON_THROW(type_error::create(307, "cannot use erase() with " + type_name())); } } - else - { - throw std::domain_error("cannot use at() with " + type_name()); - } + + return result; } /*! - @brief access specified object element with bounds checking + @brief remove elements given an iterator range - Returns a reference to the element at with specified key @a key, with - bounds checking. + Removes the element specified by the range `[first; last)`. The iterator + @a first does not need to be dereferenceable if `first == last`: erasing + an empty range is a no-op. - @param[in] key key of the element to access + If called on a primitive type other than `null`, the resulting JSON value + will be `null`. - @return reference to the element at key @a key + @param[in] first iterator to the beginning of the range to remove + @param[in] last iterator past the end of the range to remove + @return Iterator following the last removed element. If the iterator @a + second refers to the last element, the `end()` iterator is returned. - @throw std::domain_error if the JSON value is not an object; example: - `"cannot use at() with boolean"` - @throw std::out_of_range if the key @a key is is not stored in the object; - that is, `find(key) == end()`; example: `"key "the fast" not found"` + @tparam IteratorType an @ref iterator or @ref const_iterator - @complexity Logarithmic in the size of the container. + @post Invalidates iterators and references at or after the point of the + erase, including the `end()` iterator. - @liveexample{The example below shows how object elements can be read and - written using `at()`.,at__object_t_key_type} + @throw type_error.307 if called on a `null` value; example: `"cannot use + erase() with null"` + @throw invalid_iterator.203 if called on iterators which does not belong + to the current JSON value; example: `"iterators do not fit current value"` + @throw invalid_iterator.204 if called on a primitive type with invalid + iterators (i.e., if `first != begin()` and `last != end()`); example: + `"iterators out of range"` - @sa @ref operator[](const typename object_t::key_type&) for unchecked - access by reference - @sa @ref value() for access by value with a default value + @complexity The complexity depends on the type: + - objects: `log(size()) + std::distance(first, last)` + - arrays: linear in the distance between @a first and @a last, plus linear + in the distance between @a last and end of the container + - strings: linear in the length of the string + - other types: constant + + @liveexample{The example shows the result of `erase()` for different JSON + types.,erase__IteratorType_IteratorType} + + @sa @ref erase(IteratorType) -- removes the element at a given position + @sa @ref erase(const typename object_t::key_type&) -- removes the element + from an object at the given key + @sa @ref erase(const size_type) -- removes the element from an array at + the given index @since version 1.0.0 */ - reference at(const typename object_t::key_type& key) + template::value or + std::is_same::value, int>::type + = 0> + IteratorType erase(IteratorType first, IteratorType last) { - // at only works for objects - if (is_object()) - { - try - { - return m_value.object->at(key); - } - catch (std::out_of_range&) - { - // create better exception explanation - throw std::out_of_range("key '" + key + "' not found"); - } - } - else + // make sure iterator fits the current value + if (this != first.m_object or this != last.m_object) { - throw std::domain_error("cannot use at() with " + type_name()); + JSON_THROW(invalid_iterator::create(203, "iterators do not fit current value")); } - } - - /*! - @brief access specified object element with bounds checking - - Returns a const reference to the element at with specified key @a key, - with bounds checking. - - @param[in] key key of the element to access - @return const reference to the element at key @a key + IteratorType result = end(); - @throw std::domain_error if the JSON value is not an object; example: - `"cannot use at() with boolean"` - @throw std::out_of_range if the key @a key is is not stored in the object; - that is, `find(key) == end()`; example: `"key "the fast" not found"` + switch (m_type) + { + case value_t::boolean: + case value_t::number_float: + case value_t::number_integer: + case value_t::number_unsigned: + case value_t::string: + { + if (not first.m_it.primitive_iterator.is_begin() or not last.m_it.primitive_iterator.is_end()) + { + JSON_THROW(invalid_iterator::create(204, "iterators out of range")); + } - @complexity Logarithmic in the size of the container. + if (is_string()) + { + AllocatorType alloc; + alloc.destroy(m_value.string); + alloc.deallocate(m_value.string, 1); + m_value.string = nullptr; + } - @liveexample{The example below shows how object elements can be read using - `at()`.,at__object_t_key_type_const} + m_type = value_t::null; + assert_invariant(); + break; + } - @sa @ref operator[](const typename object_t::key_type&) for unchecked - access by reference - @sa @ref value() for access by value with a default value + case value_t::object: + { + result.m_it.object_iterator = m_value.object->erase(first.m_it.object_iterator, + last.m_it.object_iterator); + break; + } - @since version 1.0.0 - */ - const_reference at(const typename object_t::key_type& key) const - { - // at only works for objects - if (is_object()) - { - try + case value_t::array: { - return m_value.object->at(key); + result.m_it.array_iterator = m_value.array->erase(first.m_it.array_iterator, + last.m_it.array_iterator); + break; } - catch (std::out_of_range&) + + default: { - // create better exception explanation - throw std::out_of_range("key '" + key + "' not found"); + JSON_THROW(type_error::create(307, "cannot use erase() with " + type_name())); } } - else - { - throw std::domain_error("cannot use at() with " + type_name()); - } + + return result; } /*! - @brief access specified array element + @brief remove element from a JSON object given a key - Returns a reference to the element at specified location @a idx. + Removes elements from a JSON object with the key value @a key. - @note If @a idx is beyond the range of the array (i.e., `idx >= size()`), - then the array is silently filled up with `null` values to make `idx` a - valid reference to the last stored element. + @param[in] key value of the elements to remove - @param[in] idx index of the element to access + @return Number of elements removed. If @a ObjectType is the default + `std::map` type, the return value will always be `0` (@a key was not + found) or `1` (@a key was found). - @return reference to the element at index @a idx + @post References and iterators to the erased elements are invalidated. + Other references and iterators are not affected. + + @throw type_error.307 when called on a type other than JSON object; + example: `"cannot use erase() with null"` - @throw std::domain_error if JSON is not an array or null; example: - `"cannot use operator[] with string"` + @complexity `log(size()) + count(key)` - @complexity Constant if @a idx is in the range of the array. Otherwise - linear in `idx - size()`. + @liveexample{The example shows the effect of `erase()`.,erase__key_type} - @liveexample{The example below shows how array elements can be read and - written using `[]` operator. Note the addition of `null` - values.,operatorarray__size_type} + @sa @ref erase(IteratorType) -- removes the element at a given position + @sa @ref erase(IteratorType, IteratorType) -- removes the elements in + the given range + @sa @ref erase(const size_type) -- removes the element from an array at + the given index @since version 1.0.0 */ - reference operator[](size_type idx) + size_type erase(const typename object_t::key_type& key) { - // implicitly convert null value to an empty array - if (is_null()) + // this erase only works for objects + if (is_object()) { - m_type = value_t::array; - m_value.array = create(); - assert_invariant(); + return m_value.object->erase(key); } - // operator[] only works for arrays - if (is_array()) - { - // fill up array with null values if given idx is outside range - if (idx >= m_value.array->size()) - { - m_value.array->insert(m_value.array->end(), - idx - m_value.array->size() + 1, - basic_json()); - } - - return m_value.array->operator[](idx); - } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + JSON_THROW(type_error::create(307, "cannot use erase() with " + type_name())); } /*! - @brief access specified array element + @brief remove element from a JSON array given an index - Returns a const reference to the element at specified location @a idx. + Removes element from a JSON array at the index @a idx. - @param[in] idx index of the element to access + @param[in] idx index of the element to remove - @return const reference to the element at index @a idx + @throw type_error.307 when called on a type other than JSON object; + example: `"cannot use erase() with null"` + @throw out_of_range.401 when `idx >= size()`; example: `"array index 17 + is out of range"` - @throw std::domain_error if JSON is not an array; example: `"cannot use - operator[] with null"` + @complexity Linear in distance between @a idx and the end of the container. - @complexity Constant. + @liveexample{The example shows the effect of `erase()`.,erase__size_type} - @liveexample{The example below shows how array elements can be read using - the `[]` operator.,operatorarray__size_type_const} + @sa @ref erase(IteratorType) -- removes the element at a given position + @sa @ref erase(IteratorType, IteratorType) -- removes the elements in + the given range + @sa @ref erase(const typename object_t::key_type&) -- removes the element + from an object at the given key @since version 1.0.0 */ - const_reference operator[](size_type idx) const + void erase(const size_type idx) { - // const operator[] only works for arrays + // this erase only works for arrays if (is_array()) { - return m_value.array->operator[](idx); + if (idx >= size()) + { + JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range")); + } + + m_value.array->erase(m_value.array->begin() + static_cast(idx)); } else { - throw std::domain_error("cannot use operator[] with " + type_name()); + JSON_THROW(type_error::create(307, "cannot use erase() with " + type_name())); } } - /*! - @brief access specified object element + /// @} + - Returns a reference to the element at with specified key @a key. + //////////// + // lookup // + //////////// - @note If @a key is not found in the object, then it is silently added to - the object and filled with a `null` value to make `key` a valid reference. - In case the value was `null` before, it is converted to an object. + /// @name lookup + /// @{ - @param[in] key key of the element to access + /*! + @brief find an element in a JSON object - @return reference to the element at key @a key + Finds an element in a JSON object with key equivalent to @a key. If the + element is not found or the JSON value is not an object, end() is + returned. - @throw std::domain_error if JSON is not an object or null; example: - `"cannot use operator[] with string"` + @note This method always returns @ref end() when executed on a JSON type + that is not an object. - @complexity Logarithmic in the size of the container. + @param[in] key key value of the element to search for - @liveexample{The example below shows how object elements can be read and - written using the `[]` operator.,operatorarray__key_type} + @return Iterator to an element with key equivalent to @a key. If no such + element is found or the JSON value is not an object, past-the-end (see + @ref end()) iterator is returned. - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref value() for access by value with a default value + @complexity Logarithmic in the size of the JSON object. + + @liveexample{The example shows how `find()` is used.,find__key_type} @since version 1.0.0 */ - reference operator[](const typename object_t::key_type& key) + iterator find(typename object_t::key_type key) { - // implicitly convert null value to an empty object - if (is_null()) - { - m_type = value_t::object; - m_value.object = create(); - assert_invariant(); - } + auto result = end(); - // operator[] only works for objects if (is_object()) { - return m_value.object->operator[](key); - } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); + result.m_it.object_iterator = m_value.object->find(key); } + + return result; } /*! - @brief read-only access specified object element + @brief find an element in a JSON object + @copydoc find(typename object_t::key_type) + */ + const_iterator find(typename object_t::key_type key) const + { + auto result = cend(); - Returns a const reference to the element at with specified key @a key. No - bounds checking is performed. + if (is_object()) + { + result.m_it.object_iterator = m_value.object->find(key); + } - @warning If the element with key @a key does not exist, the behavior is - undefined. + return result; + } - @param[in] key key of the element to access + /*! + @brief returns the number of occurrences of a key in a JSON object - @return const reference to the element at key @a key + Returns the number of elements with key @a key. If ObjectType is the + default `std::map` type, the return value will always be `0` (@a key was + not found) or `1` (@a key was found). - @pre The element with key @a key must exist. **This precondition is - enforced with an assertion.** + @note This method always returns `0` when executed on a JSON type that is + not an object. - @throw std::domain_error if JSON is not an object; example: `"cannot use - operator[] with null"` + @param[in] key key value of the element to count - @complexity Logarithmic in the size of the container. + @return Number of elements with key @a key. If the JSON value is not an + object, the return value will be `0`. - @liveexample{The example below shows how object elements can be read using - the `[]` operator.,operatorarray__key_type_const} + @complexity Logarithmic in the size of the JSON object. - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref value() for access by value with a default value + @liveexample{The example shows how `count()` is used.,count} @since version 1.0.0 */ - const_reference operator[](const typename object_t::key_type& key) const + size_type count(typename object_t::key_type key) const { - // const operator[] only works for objects - if (is_object()) - { - assert(m_value.object->find(key) != m_value.object->end()); - return m_value.object->find(key)->second; - } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + // return 0 for all nonobject types + return is_object() ? m_value.object->count(key) : 0; } - /*! - @brief access specified object element + /// @} - Returns a reference to the element at with specified key @a key. - @note If @a key is not found in the object, then it is silently added to - the object and filled with a `null` value to make `key` a valid reference. - In case the value was `null` before, it is converted to an object. + /////////////// + // iterators // + /////////////// - @param[in] key key of the element to access + /// @name iterators + /// @{ - @return reference to the element at key @a key + /*! + @brief returns an iterator to the first element + + Returns an iterator to the first element. - @throw std::domain_error if JSON is not an object or null; example: - `"cannot use operator[] with string"` + @image html range-begin-end.svg "Illustration from cppreference.com" - @complexity Logarithmic in the size of the container. + @return iterator to the first element - @liveexample{The example below shows how object elements can be read and - written using the `[]` operator.,operatorarray__key_type} + @complexity Constant. - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref value() for access by value with a default value + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is constant. + + @liveexample{The following code shows an example for `begin()`.,begin} + + @sa @ref cbegin() -- returns a const iterator to the beginning + @sa @ref end() -- returns an iterator to the end + @sa @ref cend() -- returns a const iterator to the end @since version 1.0.0 */ - template - reference operator[](T * (&key)[n]) + iterator begin() noexcept { - return operator[](static_cast(key)); + iterator result(this); + result.set_begin(); + return result; } /*! - @brief read-only access specified object element - - Returns a const reference to the element at with specified key @a key. No - bounds checking is performed. + @copydoc basic_json::cbegin() + */ + const_iterator begin() const noexcept + { + return cbegin(); + } - @warning If the element with key @a key does not exist, the behavior is - undefined. + /*! + @brief returns a const iterator to the first element - @note This function is required for compatibility reasons with Clang. + Returns a const iterator to the first element. - @param[in] key key of the element to access + @image html range-begin-end.svg "Illustration from cppreference.com" - @return const reference to the element at key @a key + @return const iterator to the first element - @throw std::domain_error if JSON is not an object; example: `"cannot use - operator[] with null"` + @complexity Constant. - @complexity Logarithmic in the size of the container. + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is constant. + - Has the semantics of `const_cast(*this).begin()`. - @liveexample{The example below shows how object elements can be read using - the `[]` operator.,operatorarray__key_type_const} + @liveexample{The following code shows an example for `cbegin()`.,cbegin} - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref value() for access by value with a default value + @sa @ref begin() -- returns an iterator to the beginning + @sa @ref end() -- returns an iterator to the end + @sa @ref cend() -- returns a const iterator to the end @since version 1.0.0 */ - template - const_reference operator[](T * (&key)[n]) const + const_iterator cbegin() const noexcept { - return operator[](static_cast(key)); + const_iterator result(this); + result.set_begin(); + return result; } /*! - @brief access specified object element - - Returns a reference to the element at with specified key @a key. + @brief returns an iterator to one past the last element - @note If @a key is not found in the object, then it is silently added to - the object and filled with a `null` value to make `key` a valid reference. - In case the value was `null` before, it is converted to an object. + Returns an iterator to one past the last element. - @param[in] key key of the element to access + @image html range-begin-end.svg "Illustration from cppreference.com" - @return reference to the element at key @a key + @return iterator one past the last element - @throw std::domain_error if JSON is not an object or null; example: - `"cannot use operator[] with string"` + @complexity Constant. - @complexity Logarithmic in the size of the container. + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is constant. - @liveexample{The example below shows how object elements can be read and - written using the `[]` operator.,operatorarray__key_type} + @liveexample{The following code shows an example for `end()`.,end} - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref value() for access by value with a default value + @sa @ref cend() -- returns a const iterator to the end + @sa @ref begin() -- returns an iterator to the beginning + @sa @ref cbegin() -- returns a const iterator to the beginning - @since version 1.1.0 + @since version 1.0.0 */ - template - reference operator[](T* key) + iterator end() noexcept { - // implicitly convert null to object - if (is_null()) - { - m_type = value_t::object; - m_value = value_t::object; - assert_invariant(); - } + iterator result(this); + result.set_end(); + return result; + } - // at only works for objects - if (is_object()) - { - return m_value.object->operator[](key); - } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + /*! + @copydoc basic_json::cend() + */ + const_iterator end() const noexcept + { + return cend(); } - /*! - @brief read-only access specified object element + /*! + @brief returns a const iterator to one past the last element + + Returns a const iterator to one past the last element. + + @image html range-begin-end.svg "Illustration from cppreference.com" + + @return const iterator one past the last element + + @complexity Constant. + + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is constant. + - Has the semantics of `const_cast(*this).end()`. + + @liveexample{The following code shows an example for `cend()`.,cend} - Returns a const reference to the element at with specified key @a key. No - bounds checking is performed. + @sa @ref end() -- returns an iterator to the end + @sa @ref begin() -- returns an iterator to the beginning + @sa @ref cbegin() -- returns a const iterator to the beginning - @warning If the element with key @a key does not exist, the behavior is - undefined. + @since version 1.0.0 + */ + const_iterator cend() const noexcept + { + const_iterator result(this); + result.set_end(); + return result; + } - @param[in] key key of the element to access + /*! + @brief returns an iterator to the reverse-beginning - @return const reference to the element at key @a key + Returns an iterator to the reverse-beginning; that is, the last element. - @pre The element with key @a key must exist. **This precondition is - enforced with an assertion.** + @image html range-rbegin-rend.svg "Illustration from cppreference.com" - @throw std::domain_error if JSON is not an object; example: `"cannot use - operator[] with null"` + @complexity Constant. - @complexity Logarithmic in the size of the container. + @requirement This function helps `basic_json` satisfying the + [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) + requirements: + - The complexity is constant. + - Has the semantics of `reverse_iterator(end())`. - @liveexample{The example below shows how object elements can be read using - the `[]` operator.,operatorarray__key_type_const} + @liveexample{The following code shows an example for `rbegin()`.,rbegin} - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref value() for access by value with a default value + @sa @ref crbegin() -- returns a const reverse iterator to the beginning + @sa @ref rend() -- returns a reverse iterator to the end + @sa @ref crend() -- returns a const reverse iterator to the end - @since version 1.1.0 + @since version 1.0.0 */ - template - const_reference operator[](T* key) const + reverse_iterator rbegin() noexcept { - // at only works for objects - if (is_object()) - { - assert(m_value.object->find(key) != m_value.object->end()); - return m_value.object->find(key)->second; - } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + return reverse_iterator(end()); } /*! - @brief access specified object element with default value - - Returns either a copy of an object's element at the specified key @a key - or a given default value if no element with key @a key exists. - - The function is basically equivalent to executing - @code {.cpp} - try { - return at(key); - } catch(std::out_of_range) { - return default_value; + @copydoc basic_json::crbegin() + */ + const_reverse_iterator rbegin() const noexcept + { + return crbegin(); } - @endcode - - @note Unlike @ref at(const typename object_t::key_type&), this function - does not throw if the given key @a key was not found. - - @note Unlike @ref operator[](const typename object_t::key_type& key), this - function does not implicitly add an element to the position defined by @a - key. This function is furthermore also applicable to const objects. - @param[in] key key of the element to access - @param[in] default_value the value to return if @a key is not found + /*! + @brief returns an iterator to the reverse-end - @tparam ValueType type compatible to JSON values, for instance `int` for - JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for - JSON arrays. Note the type of the expected value at @a key and the default - value @a default_value must be compatible. + Returns an iterator to the reverse-end; that is, one before the first + element. - @return copy of the element at key @a key or @a default_value if @a key - is not found + @image html range-rbegin-rend.svg "Illustration from cppreference.com" - @throw std::domain_error if JSON is not an object; example: `"cannot use - value() with null"` + @complexity Constant. - @complexity Logarithmic in the size of the container. + @requirement This function helps `basic_json` satisfying the + [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) + requirements: + - The complexity is constant. + - Has the semantics of `reverse_iterator(begin())`. - @liveexample{The example below shows how object elements can be queried - with a default value.,basic_json__value} + @liveexample{The following code shows an example for `rend()`.,rend} - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref operator[](const typename object_t::key_type&) for unchecked - access by reference + @sa @ref crend() -- returns a const reverse iterator to the end + @sa @ref rbegin() -- returns a reverse iterator to the beginning + @sa @ref crbegin() -- returns a const reverse iterator to the beginning @since version 1.0.0 */ - template::value, int>::type = 0> - ValueType value(const typename object_t::key_type& key, ValueType default_value) const + reverse_iterator rend() noexcept { - // at only works for objects - if (is_object()) - { - // if key is found, return value and given default value otherwise - const auto it = find(key); - if (it != end()) - { - return *it; - } - else - { - return default_value; - } - } - else - { - throw std::domain_error("cannot use value() with " + type_name()); - } + return reverse_iterator(begin()); } /*! - @brief overload for a default value of type const char* - @copydoc basic_json::value(const typename object_t::key_type&, ValueType) const + @copydoc basic_json::crend() */ - string_t value(const typename object_t::key_type& key, const char* default_value) const + const_reverse_iterator rend() const noexcept { - return value(key, string_t(default_value)); + return crend(); } /*! - @brief access specified object element via JSON Pointer with default value - - Returns either a copy of an object's element at the specified key @a key - or a given default value if no element with key @a key exists. - - The function is basically equivalent to executing - @code {.cpp} - try { - return at(ptr); - } catch(std::out_of_range) { - return default_value; - } - @endcode - - @note Unlike @ref at(const json_pointer&), this function does not throw - if the given key @a key was not found. - - @param[in] ptr a JSON pointer to the element to access - @param[in] default_value the value to return if @a ptr found no value - - @tparam ValueType type compatible to JSON values, for instance `int` for - JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for - JSON arrays. Note the type of the expected value at @a key and the default - value @a default_value must be compatible. + @brief returns a const reverse iterator to the last element - @return copy of the element at key @a key or @a default_value if @a key - is not found + Returns a const iterator to the reverse-beginning; that is, the last + element. - @throw std::domain_error if JSON is not an object; example: `"cannot use - value() with null"` + @image html range-rbegin-rend.svg "Illustration from cppreference.com" - @complexity Logarithmic in the size of the container. + @complexity Constant. - @liveexample{The example below shows how object elements can be queried - with a default value.,basic_json__value_ptr} + @requirement This function helps `basic_json` satisfying the + [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) + requirements: + - The complexity is constant. + - Has the semantics of `const_cast(*this).rbegin()`. - @sa @ref operator[](const json_pointer&) for unchecked access by reference + @liveexample{The following code shows an example for `crbegin()`.,crbegin} - @since version 2.0.2 - */ - template::value, int>::type = 0> - ValueType value(const json_pointer& ptr, ValueType default_value) const - { - // at only works for objects - if (is_object()) - { - // if pointer resolves a value, return it or use default value - try - { - return ptr.get_checked(this); - } - catch (std::out_of_range&) - { - return default_value; - } - } - else - { - throw std::domain_error("cannot use value() with " + type_name()); - } - } + @sa @ref rbegin() -- returns a reverse iterator to the beginning + @sa @ref rend() -- returns a reverse iterator to the end + @sa @ref crend() -- returns a const reverse iterator to the end - /*! - @brief overload for a default value of type const char* - @copydoc basic_json::value(const json_pointer&, ValueType) const + @since version 1.0.0 */ - string_t value(const json_pointer& ptr, const char* default_value) const + const_reverse_iterator crbegin() const noexcept { - return value(ptr, string_t(default_value)); + return const_reverse_iterator(cend()); } /*! - @brief access the first element + @brief returns a const reverse iterator to one before the first - Returns a reference to the first element in the container. For a JSON - container `c`, the expression `c.front()` is equivalent to `*c.begin()`. + Returns a const reverse iterator to the reverse-end; that is, one before + the first element. - @return In case of a structured type (array or object), a reference to the - first element is returned. In cast of number, string, or boolean values, a - reference to the value is returned. + @image html range-rbegin-rend.svg "Illustration from cppreference.com" @complexity Constant. - @pre The JSON value must not be `null` (would throw `std::out_of_range`) - or an empty array or object (undefined behavior, **guarded by - assertions**). - @post The JSON value remains unchanged. - - @throw std::out_of_range when called on `null` value + @requirement This function helps `basic_json` satisfying the + [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) + requirements: + - The complexity is constant. + - Has the semantics of `const_cast(*this).rend()`. - @liveexample{The following code shows an example for `front()`.,front} + @liveexample{The following code shows an example for `crend()`.,crend} - @sa @ref back() -- access the last element + @sa @ref rend() -- returns a reverse iterator to the end + @sa @ref rbegin() -- returns a reverse iterator to the beginning + @sa @ref crbegin() -- returns a const reverse iterator to the beginning @since version 1.0.0 */ - reference front() + const_reverse_iterator crend() const noexcept + { + return const_reverse_iterator(cbegin()); + } + + private: + // forward declaration + template class iteration_proxy; + + public: + /*! + @brief wrapper to access iterator member functions in range-based for + + This function allows to access @ref iterator::key() and @ref + iterator::value() during range-based for loops. In these loops, a + reference to the JSON values is returned, so there is no access to the + underlying iterator. + + @liveexample{The following code shows how the wrapper is used,iterator_wrapper} + + @note The name of this function is not yet final and may change in the + future. + */ + static iteration_proxy iterator_wrapper(reference cont) { - return *begin(); + return iteration_proxy(cont); } /*! - @copydoc basic_json::front() + @copydoc iterator_wrapper(reference) */ - const_reference front() const + static iteration_proxy iterator_wrapper(const_reference cont) { - return *cbegin(); + return iteration_proxy(cont); } + /// @} + + + ////////////// + // capacity // + ////////////// + + /// @name capacity + /// @{ + /*! - @brief access the last element + @brief checks whether the container is empty - Returns a reference to the last element in the container. For a JSON - container `c`, the expression `c.back()` is equivalent to - @code {.cpp} - auto tmp = c.end(); - --tmp; - return *tmp; - @endcode + Checks if a JSON value has no elements. - @return In case of a structured type (array or object), a reference to the - last element is returned. In cast of number, string, or boolean values, a - reference to the value is returned. + @return The return value depends on the different types and is + defined as follows: + Value type | return value + ----------- | ------------- + null | `true` + boolean | `false` + string | `false` + number | `false` + object | result of function `object_t::empty()` + array | result of function `array_t::empty()` - @complexity Constant. + @note This function does not return whether a string stored as JSON value + is empty - it returns whether the JSON container itself is empty which is + false in the case of a string. - @pre The JSON value must not be `null` (would throw `std::out_of_range`) - or an empty array or object (undefined behavior, **guarded by - assertions**). - @post The JSON value remains unchanged. + @complexity Constant, as long as @ref array_t and @ref object_t satisfy + the Container concept; that is, their `empty()` functions have constant + complexity. - @throw std::out_of_range when called on `null` value. + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is constant. + - Has the semantics of `begin() == end()`. - @liveexample{The following code shows an example for `back()`.,back} + @liveexample{The following code uses `empty()` to check if a JSON + object contains any elements.,empty} - @sa @ref front() -- access the first element + @sa @ref size() -- returns the number of elements @since version 1.0.0 */ - reference back() + bool empty() const noexcept { - auto tmp = end(); - --tmp; - return *tmp; - } + switch (m_type) + { + case value_t::null: + { + // null values are empty + return true; + } - /*! - @copydoc basic_json::back() - */ - const_reference back() const - { - auto tmp = cend(); - --tmp; - return *tmp; - } + case value_t::array: + { + // delegate call to array_t::empty() + return m_value.array->empty(); + } - /*! - @brief remove element given an iterator + case value_t::object: + { + // delegate call to object_t::empty() + return m_value.object->empty(); + } - Removes the element specified by iterator @a pos. The iterator @a pos must - be valid and dereferenceable. Thus the `end()` iterator (which is valid, - but is not dereferenceable) cannot be used as a value for @a pos. + default: + { + // all other types are nonempty + return false; + } + } + } - If called on a primitive type other than `null`, the resulting JSON value - will be `null`. + /*! + @brief returns the number of elements - @param[in] pos iterator to the element to remove - @return Iterator following the last removed element. If the iterator @a - pos refers to the last element, the `end()` iterator is returned. + Returns the number of elements in a JSON value. - @tparam IteratorType an @ref iterator or @ref const_iterator + @return The return value depends on the different types and is + defined as follows: + Value type | return value + ----------- | ------------- + null | `0` + boolean | `1` + string | `1` + number | `1` + object | result of function object_t::size() + array | result of function array_t::size() - @post Invalidates iterators and references at or after the point of the - erase, including the `end()` iterator. + @note This function does not return the length of a string stored as JSON + value - it returns the number of elements in the JSON value which is 1 in + the case of a string. - @throw std::domain_error if called on a `null` value; example: `"cannot - use erase() with null"` - @throw std::domain_error if called on an iterator which does not belong to - the current JSON value; example: `"iterator does not fit current value"` - @throw std::out_of_range if called on a primitive type with invalid - iterator (i.e., any iterator which is not `begin()`); example: `"iterator - out of range"` + @complexity Constant, as long as @ref array_t and @ref object_t satisfy + the Container concept; that is, their size() functions have constant + complexity. - @complexity The complexity depends on the type: - - objects: amortized constant - - arrays: linear in distance between pos and the end of the container - - strings: linear in the length of the string - - other types: constant + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is constant. + - Has the semantics of `std::distance(begin(), end())`. - @liveexample{The example shows the result of `erase()` for different JSON - types.,erase__IteratorType} + @liveexample{The following code calls `size()` on the different value + types.,size} - @sa @ref erase(IteratorType, IteratorType) -- removes the elements in - the given range - @sa @ref erase(const typename object_t::key_type&) -- removes the element - from an object at the given key - @sa @ref erase(const size_type) -- removes the element from an array at - the given index + @sa @ref empty() -- checks whether the container is empty + @sa @ref max_size() -- returns the maximal number of elements @since version 1.0.0 */ - template::value or - std::is_same::value, int>::type - = 0> - IteratorType erase(IteratorType pos) + size_type size() const noexcept { - // make sure iterator fits the current value - if (this != pos.m_object) - { - throw std::domain_error("iterator does not fit current value"); - } - - IteratorType result = end(); - switch (m_type) { - case value_t::boolean: - case value_t::number_float: - case value_t::number_integer: - case value_t::number_unsigned: - case value_t::string: + case value_t::null: { - if (not pos.m_it.primitive_iterator.is_begin()) - { - throw std::out_of_range("iterator out of range"); - } - - if (is_string()) - { - AllocatorType alloc; - alloc.destroy(m_value.string); - alloc.deallocate(m_value.string, 1); - m_value.string = nullptr; - } + // null values are empty + return 0; + } - m_type = value_t::null; - assert_invariant(); - break; + case value_t::array: + { + // delegate call to array_t::size() + return m_value.array->size(); } case value_t::object: { - result.m_it.object_iterator = m_value.object->erase(pos.m_it.object_iterator); - break; + // delegate call to object_t::size() + return m_value.object->size(); + } + + default: + { + // all other types have size 1 + return 1; } + } + } + + /*! + @brief returns the maximum possible number of elements + + Returns the maximum number of elements a JSON value is able to hold due to + system or library implementation limitations, i.e. `std::distance(begin(), + end())` for the JSON value. + + @return The return value depends on the different types and is + defined as follows: + Value type | return value + ----------- | ------------- + null | `0` (same as `size()`) + boolean | `1` (same as `size()`) + string | `1` (same as `size()`) + number | `1` (same as `size()`) + object | result of function `object_t::max_size()` + array | result of function `array_t::max_size()` + + @complexity Constant, as long as @ref array_t and @ref object_t satisfy + the Container concept; that is, their `max_size()` functions have constant + complexity. + + @requirement This function helps `basic_json` satisfying the + [Container](http://en.cppreference.com/w/cpp/concept/Container) + requirements: + - The complexity is constant. + - Has the semantics of returning `b.size()` where `b` is the largest + possible JSON value. + @liveexample{The following code calls `max_size()` on the different value + types. Note the output is implementation specific.,max_size} + + @sa @ref size() -- returns the number of elements + + @since version 1.0.0 + */ + size_type max_size() const noexcept + { + switch (m_type) + { case value_t::array: { - result.m_it.array_iterator = m_value.array->erase(pos.m_it.array_iterator); - break; + // delegate call to array_t::max_size() + return m_value.array->max_size(); + } + + case value_t::object: + { + // delegate call to object_t::max_size() + return m_value.object->max_size(); } default: { - throw std::domain_error("cannot use erase() with " + type_name()); + // all other types have max_size() == size() + return size(); } } - - return result; } - /*! - @brief remove elements given an iterator range - - Removes the element specified by the range `[first; last)`. The iterator - @a first does not need to be dereferenceable if `first == last`: erasing - an empty range is a no-op. + /// @} - If called on a primitive type other than `null`, the resulting JSON value - will be `null`. - @param[in] first iterator to the beginning of the range to remove - @param[in] last iterator past the end of the range to remove - @return Iterator following the last removed element. If the iterator @a - second refers to the last element, the `end()` iterator is returned. + /////////////// + // modifiers // + /////////////// - @tparam IteratorType an @ref iterator or @ref const_iterator + /// @name modifiers + /// @{ - @post Invalidates iterators and references at or after the point of the - erase, including the `end()` iterator. + /*! + @brief clears the contents - @throw std::domain_error if called on a `null` value; example: `"cannot - use erase() with null"` - @throw std::domain_error if called on iterators which does not belong to - the current JSON value; example: `"iterators do not fit current value"` - @throw std::out_of_range if called on a primitive type with invalid - iterators (i.e., if `first != begin()` and `last != end()`); example: - `"iterators out of range"` + Clears the content of a JSON value and resets it to the default value as + if @ref basic_json(value_t) would have been called: - @complexity The complexity depends on the type: - - objects: `log(size()) + std::distance(first, last)` - - arrays: linear in the distance between @a first and @a last, plus linear - in the distance between @a last and end of the container - - strings: linear in the length of the string - - other types: constant + Value type | initial value + ----------- | ------------- + null | `null` + boolean | `false` + string | `""` + number | `0` + object | `{}` + array | `[]` - @liveexample{The example shows the result of `erase()` for different JSON - types.,erase__IteratorType_IteratorType} + @complexity Linear in the size of the JSON value. - @sa @ref erase(IteratorType) -- removes the element at a given position - @sa @ref erase(const typename object_t::key_type&) -- removes the element - from an object at the given key - @sa @ref erase(const size_type) -- removes the element from an array at - the given index + @liveexample{The example below shows the effect of `clear()` to different + JSON types.,clear} @since version 1.0.0 */ - template::value or - std::is_same::value, int>::type - = 0> - IteratorType erase(IteratorType first, IteratorType last) + void clear() noexcept { - // make sure iterator fits the current value - if (this != first.m_object or this != last.m_object) - { - throw std::domain_error("iterators do not fit current value"); - } - - IteratorType result = end(); - switch (m_type) { - case value_t::boolean: - case value_t::number_float: case value_t::number_integer: + { + m_value.number_integer = 0; + break; + } + case value_t::number_unsigned: - case value_t::string: { - if (not first.m_it.primitive_iterator.is_begin() or not last.m_it.primitive_iterator.is_end()) - { - throw std::out_of_range("iterators out of range"); - } + m_value.number_unsigned = 0; + break; + } - if (is_string()) - { - AllocatorType alloc; - alloc.destroy(m_value.string); - alloc.deallocate(m_value.string, 1); - m_value.string = nullptr; - } + case value_t::number_float: + { + m_value.number_float = 0.0; + break; + } - m_type = value_t::null; - assert_invariant(); + case value_t::boolean: + { + m_value.boolean = false; break; } - case value_t::object: + case value_t::string: { - result.m_it.object_iterator = m_value.object->erase(first.m_it.object_iterator, - last.m_it.object_iterator); + m_value.string->clear(); break; } case value_t::array: { - result.m_it.array_iterator = m_value.array->erase(first.m_it.array_iterator, - last.m_it.array_iterator); + m_value.array->clear(); + break; + } + + case value_t::object: + { + m_value.object->clear(); break; } default: { - throw std::domain_error("cannot use erase() with " + type_name()); + break; } } - - return result; } /*! - @brief remove element from a JSON object given a key - - Removes elements from a JSON object with the key value @a key. - - @param[in] key value of the elements to remove - - @return Number of elements removed. If @a ObjectType is the default - `std::map` type, the return value will always be `0` (@a key was not - found) or `1` (@a key was found). + @brief add an object to an array - @post References and iterators to the erased elements are invalidated. - Other references and iterators are not affected. + Appends the given element @a val to the end of the JSON value. If the + function is called on a JSON null value, an empty array is created before + appending @a val. - @throw std::domain_error when called on a type other than JSON object; - example: `"cannot use erase() with null"` + @param[in] val the value to add to the JSON array - @complexity `log(size()) + count(key)` + @throw type_error.308 when called on a type other than JSON array or + null; example: `"cannot use push_back() with number"` - @liveexample{The example shows the effect of `erase()`.,erase__key_type} + @complexity Amortized constant. - @sa @ref erase(IteratorType) -- removes the element at a given position - @sa @ref erase(IteratorType, IteratorType) -- removes the elements in - the given range - @sa @ref erase(const size_type) -- removes the element from an array at - the given index + @liveexample{The example shows how `push_back()` and `+=` can be used to + add elements to a JSON array. Note how the `null` value was silently + converted to a JSON array.,push_back} @since version 1.0.0 */ - size_type erase(const typename object_t::key_type& key) + void push_back(basic_json&& val) { - // this erase only works for objects - if (is_object()) + // push_back only works for null objects or arrays + if (not(is_null() or is_array())) { - return m_value.object->erase(key); + JSON_THROW(type_error::create(308, "cannot use push_back() with " + type_name())); } - else + + // transform null object into an array + if (is_null()) { - throw std::domain_error("cannot use erase() with " + type_name()); + m_type = value_t::array; + m_value = value_t::array; + assert_invariant(); } + + // add element to array (move semantics) + m_value.array->push_back(std::move(val)); + // invalidate object + val.m_type = value_t::null; } /*! - @brief remove element from a JSON array given an index - - Removes element from a JSON array at the index @a idx. - - @param[in] idx index of the element to remove - - @throw std::domain_error when called on a type other than JSON array; - example: `"cannot use erase() with null"` - @throw std::out_of_range when `idx >= size()`; example: `"array index 17 - is out of range"` - - @complexity Linear in distance between @a idx and the end of the container. - - @liveexample{The example shows the effect of `erase()`.,erase__size_type} - - @sa @ref erase(IteratorType) -- removes the element at a given position - @sa @ref erase(IteratorType, IteratorType) -- removes the elements in - the given range - @sa @ref erase(const typename object_t::key_type&) -- removes the element - from an object at the given key + @brief add an object to an array + @copydoc push_back(basic_json&&) + */ + reference operator+=(basic_json&& val) + { + push_back(std::move(val)); + return *this; + } - @since version 1.0.0 + /*! + @brief add an object to an array + @copydoc push_back(basic_json&&) */ - void erase(const size_type idx) + void push_back(const basic_json& val) { - // this erase only works for arrays - if (is_array()) + // push_back only works for null objects or arrays + if (not(is_null() or is_array())) { - if (idx >= size()) - { - throw std::out_of_range("array index " + std::to_string(idx) + " is out of range"); - } - - m_value.array->erase(m_value.array->begin() + static_cast(idx)); + JSON_THROW(type_error::create(308, "cannot use push_back() with " + type_name())); } - else + + // transform null object into an array + if (is_null()) { - throw std::domain_error("cannot use erase() with " + type_name()); + m_type = value_t::array; + m_value = value_t::array; + assert_invariant(); } - } - - /// @} + // add element to array + m_value.array->push_back(val); + } - //////////// - // lookup // - //////////// - - /// @name lookup - /// @{ + /*! + @brief add an object to an array + @copydoc push_back(basic_json&&) + */ + reference operator+=(const basic_json& val) + { + push_back(val); + return *this; + } /*! - @brief find an element in a JSON object + @brief add an object to an object - Finds an element in a JSON object with key equivalent to @a key. If the - element is not found or the JSON value is not an object, end() is - returned. + Inserts the given element @a val to the JSON object. If the function is + called on a JSON null value, an empty object is created before inserting + @a val. - @param[in] key key value of the element to search for + @param[in] val the value to add to the JSON object - @return Iterator to an element with key equivalent to @a key. If no such - element is found, past-the-end (see end()) iterator is returned. + @throw type_error.308 when called on a type other than JSON object or + null; example: `"cannot use push_back() with number"` - @complexity Logarithmic in the size of the JSON object. + @complexity Logarithmic in the size of the container, O(log(`size()`)). - @liveexample{The example shows how `find()` is used.,find__key_type} + @liveexample{The example shows how `push_back()` and `+=` can be used to + add elements to a JSON object. Note how the `null` value was silently + converted to a JSON object.,push_back__object_t__value} @since version 1.0.0 */ - iterator find(typename object_t::key_type key) + void push_back(const typename object_t::value_type& val) { - auto result = end(); + // push_back only works for null objects or objects + if (not(is_null() or is_object())) + { + JSON_THROW(type_error::create(308, "cannot use push_back() with " + type_name())); + } - if (is_object()) + // transform null object into an object + if (is_null()) { - result.m_it.object_iterator = m_value.object->find(key); + m_type = value_t::object; + m_value = value_t::object; + assert_invariant(); } - return result; + // add element to array + m_value.object->insert(val); } /*! - @brief find an element in a JSON object - @copydoc find(typename object_t::key_type) + @brief add an object to an object + @copydoc push_back(const typename object_t::value_type&) */ - const_iterator find(typename object_t::key_type key) const + reference operator+=(const typename object_t::value_type& val) { - auto result = cend(); - - if (is_object()) - { - result.m_it.object_iterator = m_value.object->find(key); - } - - return result; + push_back(val); + return *this; } /*! - @brief returns the number of occurrences of a key in a JSON object + @brief add an object to an object - Returns the number of elements with key @a key. If ObjectType is the - default `std::map` type, the return value will always be `0` (@a key was - not found) or `1` (@a key was found). + This function allows to use `push_back` with an initializer list. In case - @param[in] key key value of the element to count + 1. the current value is an object, + 2. the initializer list @a init contains only two elements, and + 3. the first element of @a init is a string, - @return Number of elements with key @a key. If the JSON value is not an - object, the return value will be `0`. + @a init is converted into an object element and added using + @ref push_back(const typename object_t::value_type&). Otherwise, @a init + is converted to a JSON value and added using @ref push_back(basic_json&&). - @complexity Logarithmic in the size of the JSON object. + @param[in] init an initializer list - @liveexample{The example shows how `count()` is used.,count} + @complexity Linear in the size of the initializer list @a init. - @since version 1.0.0 + @note This function is required to resolve an ambiguous overload error, + because pairs like `{"key", "value"}` can be both interpreted as + `object_t::value_type` or `std::initializer_list`, see + https://github.com/nlohmann/json/issues/235 for more information. + + @liveexample{The example shows how initializer lists are treated as + objects when possible.,push_back__initializer_list} */ - size_type count(typename object_t::key_type key) const + void push_back(std::initializer_list init) { - // return 0 for all nonobject types - return is_object() ? m_value.object->count(key) : 0; + if (is_object() and init.size() == 2 and init.begin()->is_string()) + { + const string_t key = *init.begin(); + push_back(typename object_t::value_type(key, *(init.begin() + 1))); + } + else + { + push_back(basic_json(init)); + } } - /// @} - - - /////////////// - // iterators // - /////////////// - - /// @name iterators - /// @{ - /*! - @brief returns an iterator to the first element - - Returns an iterator to the first element. + @brief add an object to an object + @copydoc push_back(std::initializer_list) + */ + reference operator+=(std::initializer_list init) + { + push_back(init); + return *this; + } - @image html range-begin-end.svg "Illustration from cppreference.com" + /*! + @brief add an object to an array - @return iterator to the first element + Creates a JSON value from the passed parameters @a args to the end of the + JSON value. If the function is called on a JSON null value, an empty array + is created before appending the value created from @a args. - @complexity Constant. + @param[in] args arguments to forward to a constructor of @ref basic_json + @tparam Args compatible types to create a @ref basic_json object - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is constant. + @throw type_error.311 when called on a type other than JSON array or + null; example: `"cannot use emplace_back() with number"` - @liveexample{The following code shows an example for `begin()`.,begin} + @complexity Amortized constant. - @sa @ref cbegin() -- returns a const iterator to the beginning - @sa @ref end() -- returns an iterator to the end - @sa @ref cend() -- returns a const iterator to the end + @liveexample{The example shows how `push_back()` can be used to add + elements to a JSON array. Note how the `null` value was silently converted + to a JSON array.,emplace_back} - @since version 1.0.0 + @since version 2.0.8 */ - iterator begin() noexcept + template + void emplace_back(Args&& ... args) { - iterator result(this); - result.set_begin(); - return result; - } + // emplace_back only works for null objects or arrays + if (not(is_null() or is_array())) + { + JSON_THROW(type_error::create(311, "cannot use emplace_back() with " + type_name())); + } - /*! - @copydoc basic_json::cbegin() - */ - const_iterator begin() const noexcept - { - return cbegin(); + // transform null object into an array + if (is_null()) + { + m_type = value_t::array; + m_value = value_t::array; + assert_invariant(); + } + + // add element to array (perfect forwarding) + m_value.array->emplace_back(std::forward(args)...); } /*! - @brief returns a const iterator to the first element - - Returns a const iterator to the first element. + @brief add an object to an object if key does not exist - @image html range-begin-end.svg "Illustration from cppreference.com" + Inserts a new element into a JSON object constructed in-place with the + given @a args if there is no element with the key in the container. If the + function is called on a JSON null value, an empty object is created before + appending the value created from @a args. - @return const iterator to the first element + @param[in] args arguments to forward to a constructor of @ref basic_json + @tparam Args compatible types to create a @ref basic_json object - @complexity Constant. + @return a pair consisting of an iterator to the inserted element, or the + already-existing element if no insertion happened, and a bool + denoting whether the insertion took place. - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is constant. - - Has the semantics of `const_cast(*this).begin()`. + @throw type_error.311 when called on a type other than JSON object or + null; example: `"cannot use emplace() with number"` - @liveexample{The following code shows an example for `cbegin()`.,cbegin} + @complexity Logarithmic in the size of the container, O(log(`size()`)). - @sa @ref begin() -- returns an iterator to the beginning - @sa @ref end() -- returns an iterator to the end - @sa @ref cend() -- returns a const iterator to the end + @liveexample{The example shows how `emplace()` can be used to add elements + to a JSON object. Note how the `null` value was silently converted to a + JSON object. Further note how no value is added if there was already one + value stored with the same key.,emplace} - @since version 1.0.0 + @since version 2.0.8 */ - const_iterator cbegin() const noexcept + template + std::pair emplace(Args&& ... args) { - const_iterator result(this); - result.set_begin(); - return result; - } + // emplace only works for null objects or arrays + if (not(is_null() or is_object())) + { + JSON_THROW(type_error::create(311, "cannot use emplace() with " + type_name())); + } - /*! - @brief returns an iterator to one past the last element + // transform null object into an object + if (is_null()) + { + m_type = value_t::object; + m_value = value_t::object; + assert_invariant(); + } - Returns an iterator to one past the last element. + // add element to array (perfect forwarding) + auto res = m_value.object->emplace(std::forward(args)...); + // create result iterator and set iterator to the result of emplace + auto it = begin(); + it.m_it.object_iterator = res.first; - @image html range-begin-end.svg "Illustration from cppreference.com" + // return pair of iterator and boolean + return {it, res.second}; + } - @return iterator one past the last element + /*! + @brief inserts element - @complexity Constant. + Inserts element @a val before iterator @a pos. - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is constant. + @param[in] pos iterator before which the content will be inserted; may be + the end() iterator + @param[in] val element to insert + @return iterator pointing to the inserted @a val. - @liveexample{The following code shows an example for `end()`.,end} + @throw type_error.309 if called on JSON values other than arrays; + example: `"cannot use insert() with string"` + @throw invalid_iterator.202 if @a pos is not an iterator of *this; + example: `"iterator does not fit current value"` - @sa @ref cend() -- returns a const iterator to the end - @sa @ref begin() -- returns an iterator to the beginning - @sa @ref cbegin() -- returns a const iterator to the beginning + @complexity Constant plus linear in the distance between @a pos and end of + the container. + + @liveexample{The example shows how `insert()` is used.,insert} @since version 1.0.0 */ - iterator end() noexcept + iterator insert(const_iterator pos, const basic_json& val) { - iterator result(this); - result.set_end(); - return result; + // insert only works for arrays + if (is_array()) + { + // check if iterator pos fits to this JSON value + if (pos.m_object != this) + { + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); + } + + // insert to array and return iterator + iterator result(this); + result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, val); + return result; + } + + JSON_THROW(type_error::create(309, "cannot use insert() with " + type_name())); } /*! - @copydoc basic_json::cend() + @brief inserts element + @copydoc insert(const_iterator, const basic_json&) */ - const_iterator end() const noexcept + iterator insert(const_iterator pos, basic_json&& val) { - return cend(); + return insert(pos, val); } /*! - @brief returns a const iterator to one past the last element - - Returns a const iterator to one past the last element. - - @image html range-begin-end.svg "Illustration from cppreference.com" + @brief inserts elements - @return const iterator one past the last element + Inserts @a cnt copies of @a val before iterator @a pos. - @complexity Constant. + @param[in] pos iterator before which the content will be inserted; may be + the end() iterator + @param[in] cnt number of copies of @a val to insert + @param[in] val element to insert + @return iterator pointing to the first element inserted, or @a pos if + `cnt==0` - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is constant. - - Has the semantics of `const_cast(*this).end()`. + @throw type_error.309 if called on JSON values other than arrays; example: + `"cannot use insert() with string"` + @throw invalid_iterator.202 if @a pos is not an iterator of *this; + example: `"iterator does not fit current value"` - @liveexample{The following code shows an example for `cend()`.,cend} + @complexity Linear in @a cnt plus linear in the distance between @a pos + and end of the container. - @sa @ref end() -- returns an iterator to the end - @sa @ref begin() -- returns an iterator to the beginning - @sa @ref cbegin() -- returns a const iterator to the beginning + @liveexample{The example shows how `insert()` is used.,insert__count} @since version 1.0.0 */ - const_iterator cend() const noexcept + iterator insert(const_iterator pos, size_type cnt, const basic_json& val) { - const_iterator result(this); - result.set_end(); - return result; + // insert only works for arrays + if (is_array()) + { + // check if iterator pos fits to this JSON value + if (pos.m_object != this) + { + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); + } + + // insert to array and return iterator + iterator result(this); + result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, cnt, val); + return result; + } + + JSON_THROW(type_error::create(309, "cannot use insert() with " + type_name())); } /*! - @brief returns an iterator to the reverse-beginning + @brief inserts elements - Returns an iterator to the reverse-beginning; that is, the last element. + Inserts elements from range `[first, last)` before iterator @a pos. - @image html range-rbegin-rend.svg "Illustration from cppreference.com" + @param[in] pos iterator before which the content will be inserted; may be + the end() iterator + @param[in] first begin of the range of elements to insert + @param[in] last end of the range of elements to insert - @complexity Constant. + @throw type_error.309 if called on JSON values other than arrays; example: + `"cannot use insert() with string"` + @throw invalid_iterator.202 if @a pos is not an iterator of *this; + example: `"iterator does not fit current value"` + @throw invalid_iterator.210 if @a first and @a last do not belong to the + same JSON value; example: `"iterators do not fit"` + @throw invalid_iterator.211 if @a first or @a last are iterators into + container for which insert is called; example: `"passed iterators may not + belong to container"` - @requirement This function helps `basic_json` satisfying the - [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) - requirements: - - The complexity is constant. - - Has the semantics of `reverse_iterator(end())`. + @return iterator pointing to the first element inserted, or @a pos if + `first==last` - @liveexample{The following code shows an example for `rbegin()`.,rbegin} + @complexity Linear in `std::distance(first, last)` plus linear in the + distance between @a pos and end of the container. - @sa @ref crbegin() -- returns a const reverse iterator to the beginning - @sa @ref rend() -- returns a reverse iterator to the end - @sa @ref crend() -- returns a const reverse iterator to the end + @liveexample{The example shows how `insert()` is used.,insert__range} @since version 1.0.0 */ - reverse_iterator rbegin() noexcept + iterator insert(const_iterator pos, const_iterator first, const_iterator last) { - return reverse_iterator(end()); - } + // insert only works for arrays + if (not is_array()) + { + JSON_THROW(type_error::create(309, "cannot use insert() with " + type_name())); + } - /*! - @copydoc basic_json::crbegin() - */ - const_reverse_iterator rbegin() const noexcept - { - return crbegin(); + // check if iterator pos fits to this JSON value + if (pos.m_object != this) + { + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); + } + + // check if range iterators belong to the same JSON object + if (first.m_object != last.m_object) + { + JSON_THROW(invalid_iterator::create(210, "iterators do not fit")); + } + + if (first.m_object == this or last.m_object == this) + { + JSON_THROW(invalid_iterator::create(211, "passed iterators may not belong to container")); + } + + // insert to array and return iterator + iterator result(this); + result.m_it.array_iterator = m_value.array->insert( + pos.m_it.array_iterator, + first.m_it.array_iterator, + last.m_it.array_iterator); + return result; } /*! - @brief returns an iterator to the reverse-end + @brief inserts elements - Returns an iterator to the reverse-end; that is, one before the first - element. + Inserts elements from initializer list @a ilist before iterator @a pos. - @image html range-rbegin-rend.svg "Illustration from cppreference.com" + @param[in] pos iterator before which the content will be inserted; may be + the end() iterator + @param[in] ilist initializer list to insert the values from - @complexity Constant. + @throw type_error.309 if called on JSON values other than arrays; example: + `"cannot use insert() with string"` + @throw invalid_iterator.202 if @a pos is not an iterator of *this; + example: `"iterator does not fit current value"` - @requirement This function helps `basic_json` satisfying the - [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) - requirements: - - The complexity is constant. - - Has the semantics of `reverse_iterator(begin())`. + @return iterator pointing to the first element inserted, or @a pos if + `ilist` is empty - @liveexample{The following code shows an example for `rend()`.,rend} + @complexity Linear in `ilist.size()` plus linear in the distance between + @a pos and end of the container. - @sa @ref crend() -- returns a const reverse iterator to the end - @sa @ref rbegin() -- returns a reverse iterator to the beginning - @sa @ref crbegin() -- returns a const reverse iterator to the beginning + @liveexample{The example shows how `insert()` is used.,insert__ilist} @since version 1.0.0 */ - reverse_iterator rend() noexcept + iterator insert(const_iterator pos, std::initializer_list ilist) { - return reverse_iterator(begin()); - } + // insert only works for arrays + if (not is_array()) + { + JSON_THROW(type_error::create(309, "cannot use insert() with " + type_name())); + } - /*! - @copydoc basic_json::crend() - */ - const_reverse_iterator rend() const noexcept - { - return crend(); + // check if iterator pos fits to this JSON value + if (pos.m_object != this) + { + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); + } + + // insert to array and return iterator + iterator result(this); + result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, ilist); + return result; } /*! - @brief returns a const reverse iterator to the last element - - Returns a const iterator to the reverse-beginning; that is, the last - element. + @brief inserts elements - @image html range-rbegin-rend.svg "Illustration from cppreference.com" + Inserts elements from range `[first, last)`. - @complexity Constant. + @param[in] first begin of the range of elements to insert + @param[in] last end of the range of elements to insert - @requirement This function helps `basic_json` satisfying the - [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) - requirements: - - The complexity is constant. - - Has the semantics of `const_cast(*this).rbegin()`. + @throw type_error.309 if called on JSON values other than objects; example: + `"cannot use insert() with string"` + @throw invalid_iterator.202 if iterator @a first or @a last does does not + point to an object; example: `"iterators first and last must point to + objects"` + @throw invalid_iterator.210 if @a first and @a last do not belong to the + same JSON value; example: `"iterators do not fit"` - @liveexample{The following code shows an example for `crbegin()`.,crbegin} + @complexity Logarithmic: `O(N*log(size() + N))`, where `N` is the number + of elements to insert. - @sa @ref rbegin() -- returns a reverse iterator to the beginning - @sa @ref rend() -- returns a reverse iterator to the end - @sa @ref crend() -- returns a const reverse iterator to the end + @liveexample{The example shows how `insert()` is used.,insert__range_object} - @since version 1.0.0 + @since version 3.0.0 */ - const_reverse_iterator crbegin() const noexcept + void insert(const_iterator first, const_iterator last) { - return const_reverse_iterator(cend()); + // insert only works for objects + if (not is_object()) + { + JSON_THROW(type_error::create(309, "cannot use insert() with " + type_name())); + } + + // check if range iterators belong to the same JSON object + if (first.m_object != last.m_object) + { + JSON_THROW(invalid_iterator::create(210, "iterators do not fit")); + } + + // passed iterators must belong to objects + if (not first.m_object->is_object() or not first.m_object->is_object()) + { + JSON_THROW(invalid_iterator::create(202, "iterators first and last must point to objects")); + } + + m_value.object->insert(first.m_it.object_iterator, last.m_it.object_iterator); } /*! - @brief returns a const reverse iterator to one before the first + @brief exchanges the values - Returns a const reverse iterator to the reverse-end; that is, one before - the first element. + Exchanges the contents of the JSON value with those of @a other. Does not + invoke any move, copy, or swap operations on individual elements. All + iterators and references remain valid. The past-the-end iterator is + invalidated. - @image html range-rbegin-rend.svg "Illustration from cppreference.com" + @param[in,out] other JSON value to exchange the contents with @complexity Constant. - @requirement This function helps `basic_json` satisfying the - [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) - requirements: - - The complexity is constant. - - Has the semantics of `const_cast(*this).rend()`. - - @liveexample{The following code shows an example for `crend()`.,crend} - - @sa @ref rend() -- returns a reverse iterator to the end - @sa @ref rbegin() -- returns a reverse iterator to the beginning - @sa @ref crbegin() -- returns a const reverse iterator to the beginning + @liveexample{The example below shows how JSON values can be swapped with + `swap()`.,swap__reference} @since version 1.0.0 */ - const_reverse_iterator crend() const noexcept + void swap(reference other) noexcept ( + std::is_nothrow_move_constructible::value and + std::is_nothrow_move_assignable::value and + std::is_nothrow_move_constructible::value and + std::is_nothrow_move_assignable::value + ) { - return const_reverse_iterator(cbegin()); + std::swap(m_type, other.m_type); + std::swap(m_value, other.m_value); + assert_invariant(); } - private: - // forward declaration - template class iteration_proxy; - - public: /*! - @brief wrapper to access iterator member functions in range-based for - - This function allows to access @ref iterator::key() and @ref - iterator::value() during range-based for loops. In these loops, a - reference to the JSON values is returned, so there is no access to the - underlying iterator. + @brief exchanges the values - @note The name of this function is not yet final and may change in the - future. - */ - static iteration_proxy iterator_wrapper(reference cont) - { - return iteration_proxy(cont); - } + Exchanges the contents of a JSON array with those of @a other. Does not + invoke any move, copy, or swap operations on individual elements. All + iterators and references remain valid. The past-the-end iterator is + invalidated. - /*! - @copydoc iterator_wrapper(reference) - */ - static iteration_proxy iterator_wrapper(const_reference cont) - { - return iteration_proxy(cont); - } + @param[in,out] other array to exchange the contents with - /// @} + @throw type_error.310 when JSON value is not an array; example: `"cannot + use swap() with string"` + @complexity Constant. - ////////////// - // capacity // - ////////////// + @liveexample{The example below shows how arrays can be swapped with + `swap()`.,swap__array_t} - /// @name capacity - /// @{ + @since version 1.0.0 + */ + void swap(array_t& other) + { + // swap only works for arrays + if (is_array()) + { + std::swap(*(m_value.array), other); + } + else + { + JSON_THROW(type_error::create(310, "cannot use swap() with " + type_name())); + } + } /*! - @brief checks whether the container is empty - - Checks if a JSON value has no elements. - - @return The return value depends on the different types and is - defined as follows: - Value type | return value - ----------- | ------------- - null | `true` - boolean | `false` - string | `false` - number | `false` - object | result of function `object_t::empty()` - array | result of function `array_t::empty()` + @brief exchanges the values - @note This function does not return whether a string stored as JSON value - is empty - it returns whether the JSON container itself is empty which is - false in the case of a string. + Exchanges the contents of a JSON object with those of @a other. Does not + invoke any move, copy, or swap operations on individual elements. All + iterators and references remain valid. The past-the-end iterator is + invalidated. - @complexity Constant, as long as @ref array_t and @ref object_t satisfy - the Container concept; that is, their `empty()` functions have constant - complexity. + @param[in,out] other object to exchange the contents with - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is constant. - - Has the semantics of `begin() == end()`. + @throw type_error.310 when JSON value is not an object; example: + `"cannot use swap() with string"` - @liveexample{The following code uses `empty()` to check if a JSON - object contains any elements.,empty} + @complexity Constant. - @sa @ref size() -- returns the number of elements + @liveexample{The example below shows how objects can be swapped with + `swap()`.,swap__object_t} @since version 1.0.0 */ - bool empty() const noexcept + void swap(object_t& other) { - switch (m_type) + // swap only works for objects + if (is_object()) { - case value_t::null: - { - // null values are empty - return true; - } - - case value_t::array: - { - // delegate call to array_t::empty() - return m_value.array->empty(); - } - - case value_t::object: - { - // delegate call to object_t::empty() - return m_value.object->empty(); - } - - default: - { - // all other types are nonempty - return false; - } + std::swap(*(m_value.object), other); + } + else + { + JSON_THROW(type_error::create(310, "cannot use swap() with " + type_name())); } } /*! - @brief returns the number of elements - - Returns the number of elements in a JSON value. - - @return The return value depends on the different types and is - defined as follows: - Value type | return value - ----------- | ------------- - null | `0` - boolean | `1` - string | `1` - number | `1` - object | result of function object_t::size() - array | result of function array_t::size() + @brief exchanges the values - @note This function does not return the length of a string stored as JSON - value - it returns the number of elements in the JSON value which is 1 in - the case of a string. + Exchanges the contents of a JSON string with those of @a other. Does not + invoke any move, copy, or swap operations on individual elements. All + iterators and references remain valid. The past-the-end iterator is + invalidated. - @complexity Constant, as long as @ref array_t and @ref object_t satisfy - the Container concept; that is, their size() functions have constant - complexity. + @param[in,out] other string to exchange the contents with - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is constant. - - Has the semantics of `std::distance(begin(), end())`. + @throw type_error.310 when JSON value is not a string; example: `"cannot + use swap() with boolean"` - @liveexample{The following code calls `size()` on the different value - types.,size} + @complexity Constant. - @sa @ref empty() -- checks whether the container is empty - @sa @ref max_size() -- returns the maximal number of elements + @liveexample{The example below shows how strings can be swapped with + `swap()`.,swap__string_t} @since version 1.0.0 */ - size_type size() const noexcept + void swap(string_t& other) { - switch (m_type) + // swap only works for strings + if (is_string()) { - case value_t::null: - { - // null values are empty - return 0; - } + std::swap(*(m_value.string), other); + } + else + { + JSON_THROW(type_error::create(310, "cannot use swap() with " + type_name())); + } + } - case value_t::array: - { - // delegate call to array_t::size() - return m_value.array->size(); - } + /// @} - case value_t::object: - { - // delegate call to object_t::size() - return m_value.object->size(); - } + public: + ////////////////////////////////////////// + // lexicographical comparison operators // + ////////////////////////////////////////// - default: - { - // all other types have size 1 - return 1; - } - } - } + /// @name lexicographical comparison operators + /// @{ /*! - @brief returns the maximum possible number of elements - - Returns the maximum number of elements a JSON value is able to hold due to - system or library implementation limitations, i.e. `std::distance(begin(), - end())` for the JSON value. + @brief comparison: equal - @return The return value depends on the different types and is - defined as follows: - Value type | return value - ----------- | ------------- - null | `0` (same as `size()`) - boolean | `1` (same as `size()`) - string | `1` (same as `size()`) - number | `1` (same as `size()`) - object | result of function `object_t::max_size()` - array | result of function `array_t::max_size()` + Compares two JSON values for equality according to the following rules: + - Two JSON values are equal if (1) they are from the same type and (2) + their stored values are the same according to their respective + `operator==`. + - Integer and floating-point numbers are automatically converted before + comparison. Floating-point numbers are compared indirectly: two + floating-point numbers `f1` and `f2` are considered equal if neither + `f1 > f2` nor `f2 > f1` holds. Note than two NaN values are always + treated as unequal. + - Two JSON null values are equal. - @complexity Constant, as long as @ref array_t and @ref object_t satisfy - the Container concept; that is, their `max_size()` functions have constant - complexity. + @note NaN values never compare equal to themselves or to other NaN values. - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is constant. - - Has the semantics of returning `b.size()` where `b` is the largest - possible JSON value. + @param[in] lhs first JSON value to consider + @param[in] rhs second JSON value to consider + @return whether the values @a lhs and @a rhs are equal - @liveexample{The following code calls `max_size()` on the different value - types. Note the output is implementation specific.,max_size} + @complexity Linear. - @sa @ref size() -- returns the number of elements + @liveexample{The example demonstrates comparing several JSON + types.,operator__equal} @since version 1.0.0 */ - size_type max_size() const noexcept + friend bool operator==(const_reference lhs, const_reference rhs) noexcept { - switch (m_type) + const auto lhs_type = lhs.type(); + const auto rhs_type = rhs.type(); + + if (lhs_type == rhs_type) { - case value_t::array: + switch (lhs_type) { - // delegate call to array_t::max_size() - return m_value.array->max_size(); + case value_t::array: + { + return *lhs.m_value.array == *rhs.m_value.array; + } + case value_t::object: + { + return *lhs.m_value.object == *rhs.m_value.object; + } + case value_t::null: + { + return true; + } + case value_t::string: + { + return *lhs.m_value.string == *rhs.m_value.string; + } + case value_t::boolean: + { + return lhs.m_value.boolean == rhs.m_value.boolean; + } + case value_t::number_integer: + { + return lhs.m_value.number_integer == rhs.m_value.number_integer; + } + case value_t::number_unsigned: + { + return lhs.m_value.number_unsigned == rhs.m_value.number_unsigned; + } + case value_t::number_float: + { + return lhs.m_value.number_float == rhs.m_value.number_float; + } + default: + { + return false; + } } + } + else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float) + { + return static_cast(lhs.m_value.number_integer) == rhs.m_value.number_float; + } + else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer) + { + return lhs.m_value.number_float == static_cast(rhs.m_value.number_integer); + } + else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float) + { + return static_cast(lhs.m_value.number_unsigned) == rhs.m_value.number_float; + } + else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned) + { + return lhs.m_value.number_float == static_cast(rhs.m_value.number_unsigned); + } + else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer) + { + return static_cast(lhs.m_value.number_unsigned) == rhs.m_value.number_integer; + } + else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned) + { + return lhs.m_value.number_integer == static_cast(rhs.m_value.number_unsigned); + } - case value_t::object: - { - // delegate call to object_t::max_size() - return m_value.object->max_size(); - } + return false; + } - default: - { - // all other types have max_size() == size() - return size(); - } - } + /*! + @brief comparison: equal + @copydoc operator==(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator==(const_reference lhs, const ScalarType rhs) noexcept + { + return (lhs == basic_json(rhs)); + } + + /*! + @brief comparison: equal + @copydoc operator==(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator==(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) == rhs); } - /// @} + /*! + @brief comparison: not equal + Compares two JSON values for inequality by calculating `not (lhs == rhs)`. - /////////////// - // modifiers // - /////////////// + @param[in] lhs first JSON value to consider + @param[in] rhs second JSON value to consider + @return whether the values @a lhs and @a rhs are not equal - /// @name modifiers - /// @{ + @complexity Linear. + + @liveexample{The example demonstrates comparing several JSON + types.,operator__notequal} + + @since version 1.0.0 + */ + friend bool operator!=(const_reference lhs, const_reference rhs) noexcept + { + return not (lhs == rhs); + } /*! - @brief clears the contents + @brief comparison: not equal + @copydoc operator!=(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator!=(const_reference lhs, const ScalarType rhs) noexcept + { + return (lhs != basic_json(rhs)); + } - Clears the content of a JSON value and resets it to the default value as - if @ref basic_json(value_t) would have been called: + /*! + @brief comparison: not equal + @copydoc operator!=(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator!=(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) != rhs); + } - Value type | initial value - ----------- | ------------- - null | `null` - boolean | `false` - string | `""` - number | `0` - object | `{}` - array | `[]` + /*! + @brief comparison: less than - @note Floating-point numbers are set to `0.0` which will be serialized to - `0`. The vale type remains @ref number_float_t. + Compares whether one JSON value @a lhs is less than another JSON value @a + rhs according to the following rules: + - If @a lhs and @a rhs have the same type, the values are compared using + the default `<` operator. + - Integer and floating-point numbers are automatically converted before + comparison + - In case @a lhs and @a rhs have different types, the values are ignored + and the order of the types is considered, see + @ref operator<(const value_t, const value_t). - @complexity Linear in the size of the JSON value. + @param[in] lhs first JSON value to consider + @param[in] rhs second JSON value to consider + @return whether @a lhs is less than @a rhs - @liveexample{The example below shows the effect of `clear()` to different - JSON types.,clear} + @complexity Linear. + + @liveexample{The example demonstrates comparing several JSON + types.,operator__less} @since version 1.0.0 */ - void clear() noexcept + friend bool operator<(const_reference lhs, const_reference rhs) noexcept { - switch (m_type) + const auto lhs_type = lhs.type(); + const auto rhs_type = rhs.type(); + + if (lhs_type == rhs_type) { - case value_t::number_integer: + switch (lhs_type) { - m_value.number_integer = 0; - break; + case value_t::array: + { + return *lhs.m_value.array < *rhs.m_value.array; + } + case value_t::object: + { + return *lhs.m_value.object < *rhs.m_value.object; + } + case value_t::null: + { + return false; + } + case value_t::string: + { + return *lhs.m_value.string < *rhs.m_value.string; + } + case value_t::boolean: + { + return lhs.m_value.boolean < rhs.m_value.boolean; + } + case value_t::number_integer: + { + return lhs.m_value.number_integer < rhs.m_value.number_integer; + } + case value_t::number_unsigned: + { + return lhs.m_value.number_unsigned < rhs.m_value.number_unsigned; + } + case value_t::number_float: + { + return lhs.m_value.number_float < rhs.m_value.number_float; + } + default: + { + return false; + } } + } + else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float) + { + return static_cast(lhs.m_value.number_integer) < rhs.m_value.number_float; + } + else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer) + { + return lhs.m_value.number_float < static_cast(rhs.m_value.number_integer); + } + else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float) + { + return static_cast(lhs.m_value.number_unsigned) < rhs.m_value.number_float; + } + else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned) + { + return lhs.m_value.number_float < static_cast(rhs.m_value.number_unsigned); + } + else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned) + { + return lhs.m_value.number_integer < static_cast(rhs.m_value.number_unsigned); + } + else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer) + { + return static_cast(lhs.m_value.number_unsigned) < rhs.m_value.number_integer; + } - case value_t::number_unsigned: - { - m_value.number_unsigned = 0; - break; - } + // We only reach this line if we cannot compare values. In that case, + // we compare types. Note we have to call the operator explicitly, + // because MSVC has problems otherwise. + return operator<(lhs_type, rhs_type); + } - case value_t::number_float: - { - m_value.number_float = 0.0; - break; - } + /*! + @brief comparison: less than + @copydoc operator<(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator<(const_reference lhs, const ScalarType rhs) noexcept + { + return (lhs < basic_json(rhs)); + } - case value_t::boolean: - { - m_value.boolean = false; - break; - } + /*! + @brief comparison: less than + @copydoc operator<(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator<(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) < rhs); + } - case value_t::string: - { - m_value.string->clear(); - break; - } + /*! + @brief comparison: less than or equal - case value_t::array: - { - m_value.array->clear(); - break; - } + Compares whether one JSON value @a lhs is less than or equal to another + JSON value by calculating `not (rhs < lhs)`. - case value_t::object: - { - m_value.object->clear(); - break; - } + @param[in] lhs first JSON value to consider + @param[in] rhs second JSON value to consider + @return whether @a lhs is less than or equal to @a rhs - default: - { - break; - } - } + @complexity Linear. + + @liveexample{The example demonstrates comparing several JSON + types.,operator__greater} + + @since version 1.0.0 + */ + friend bool operator<=(const_reference lhs, const_reference rhs) noexcept + { + return not (rhs < lhs); } /*! - @brief add an object to an array + @brief comparison: less than or equal + @copydoc operator<=(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator<=(const_reference lhs, const ScalarType rhs) noexcept + { + return (lhs <= basic_json(rhs)); + } - Appends the given element @a val to the end of the JSON value. If the - function is called on a JSON null value, an empty array is created before - appending @a val. + /*! + @brief comparison: less than or equal + @copydoc operator<=(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator<=(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) <= rhs); + } - @param[in] val the value to add to the JSON array + /*! + @brief comparison: greater than - @throw std::domain_error when called on a type other than JSON array or - null; example: `"cannot use push_back() with number"` + Compares whether one JSON value @a lhs is greater than another + JSON value by calculating `not (lhs <= rhs)`. - @complexity Amortized constant. + @param[in] lhs first JSON value to consider + @param[in] rhs second JSON value to consider + @return whether @a lhs is greater than to @a rhs - @liveexample{The example shows how `push_back()` and `+=` can be used to - add elements to a JSON array. Note how the `null` value was silently - converted to a JSON array.,push_back} + @complexity Linear. + + @liveexample{The example demonstrates comparing several JSON + types.,operator__lessequal} @since version 1.0.0 */ - void push_back(basic_json&& val) + friend bool operator>(const_reference lhs, const_reference rhs) noexcept { - // push_back only works for null objects or arrays - if (not(is_null() or is_array())) - { - throw std::domain_error("cannot use push_back() with " + type_name()); - } - - // transform null object into an array - if (is_null()) - { - m_type = value_t::array; - m_value = value_t::array; - assert_invariant(); - } - - // add element to array (move semantics) - m_value.array->push_back(std::move(val)); - // invalidate object - val.m_type = value_t::null; + return not (lhs <= rhs); } /*! - @brief add an object to an array - @copydoc push_back(basic_json&&) + @brief comparison: greater than + @copydoc operator>(const_reference, const_reference) */ - reference operator+=(basic_json&& val) + template::value, int>::type = 0> + friend bool operator>(const_reference lhs, const ScalarType rhs) noexcept { - push_back(std::move(val)); - return *this; + return (lhs > basic_json(rhs)); } /*! - @brief add an object to an array - @copydoc push_back(basic_json&&) + @brief comparison: greater than + @copydoc operator>(const_reference, const_reference) */ - void push_back(const basic_json& val) + template::value, int>::type = 0> + friend bool operator>(const ScalarType lhs, const_reference rhs) noexcept { - // push_back only works for null objects or arrays - if (not(is_null() or is_array())) - { - throw std::domain_error("cannot use push_back() with " + type_name()); - } + return (basic_json(lhs) > rhs); + } - // transform null object into an array - if (is_null()) - { - m_type = value_t::array; - m_value = value_t::array; - assert_invariant(); - } + /*! + @brief comparison: greater than or equal - // add element to array - m_value.array->push_back(val); + Compares whether one JSON value @a lhs is greater than or equal to another + JSON value by calculating `not (lhs < rhs)`. + + @param[in] lhs first JSON value to consider + @param[in] rhs second JSON value to consider + @return whether @a lhs is greater than or equal to @a rhs + + @complexity Linear. + + @liveexample{The example demonstrates comparing several JSON + types.,operator__greaterequal} + + @since version 1.0.0 + */ + friend bool operator>=(const_reference lhs, const_reference rhs) noexcept + { + return not (lhs < rhs); } /*! - @brief add an object to an array - @copydoc push_back(basic_json&&) + @brief comparison: greater than or equal + @copydoc operator>=(const_reference, const_reference) */ - reference operator+=(const basic_json& val) + template::value, int>::type = 0> + friend bool operator>=(const_reference lhs, const ScalarType rhs) noexcept { - push_back(val); - return *this; + return (lhs >= basic_json(rhs)); } /*! - @brief add an object to an object - - Inserts the given element @a val to the JSON object. If the function is - called on a JSON null value, an empty object is created before inserting - @a val. + @brief comparison: greater than or equal + @copydoc operator>=(const_reference, const_reference) + */ + template::value, int>::type = 0> + friend bool operator>=(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) >= rhs); + } - @param[in] val the value to add to the JSON object + /// @} - @throw std::domain_error when called on a type other than JSON object or - null; example: `"cannot use push_back() with number"` + private: + ///////////////////// + // output adapters // + ///////////////////// - @complexity Logarithmic in the size of the container, O(log(`size()`)). + /// abstract output adapter interface + template + class output_adapter + { + public: + virtual void write_character(CharType c) = 0; + virtual void write_characters(const CharType* s, size_t length) = 0; + virtual ~output_adapter() {} - @liveexample{The example shows how `push_back()` and `+=` can be used to - add elements to a JSON object. Note how the `null` value was silently - converted to a JSON object.,push_back__object_t__value} + static std::shared_ptr> create(std::vector& vec) + { + return std::shared_ptr(new output_vector_adapter(vec)); + } - @since version 1.0.0 - */ - void push_back(const typename object_t::value_type& val) - { - // push_back only works for null objects or objects - if (not(is_null() or is_object())) + static std::shared_ptr> create(std::ostream& s) { - throw std::domain_error("cannot use push_back() with " + type_name()); + return std::shared_ptr(new output_stream_adapter(s)); } - // transform null object into an object - if (is_null()) + static std::shared_ptr> create(std::string& s) { - m_type = value_t::object; - m_value = value_t::object; - assert_invariant(); + return std::shared_ptr(new output_string_adapter(s)); } + }; - // add element to array - m_value.object->insert(val); - } + /// a type to simplify interfaces + template + using output_adapter_t = std::shared_ptr>; - /*! - @brief add an object to an object - @copydoc push_back(const typename object_t::value_type&) - */ - reference operator+=(const typename object_t::value_type& val) + /// output adapter for byte vectors + template + class output_vector_adapter : public output_adapter { - push_back(val); - return *this; - } + public: + output_vector_adapter(std::vector& vec) + : v(vec) + {} - /*! - @brief add an object to an object + void write_character(CharType c) override + { + v.push_back(c); + } - This function allows to use `push_back` with an initializer list. In case + void write_characters(const CharType* s, size_t length) override + { + std::copy(s, s + length, std::back_inserter(v)); + } - 1. the current value is an object, - 2. the initializer list @a init contains only two elements, and - 3. the first element of @a init is a string, + private: + std::vector& v; + }; - @a init is converted into an object element and added using - @ref push_back(const typename object_t::value_type&). Otherwise, @a init - is converted to a JSON value and added using @ref push_back(basic_json&&). + /// putput adatpter for output streams + template + class output_stream_adapter : public output_adapter + { + public: + output_stream_adapter(std::basic_ostream& s) + : stream(s) + {} - @param init an initializer list + void write_character(CharType c) override + { + stream.put(c); + } - @complexity Linear in the size of the initializer list @a init. + void write_characters(const CharType* s, size_t length) override + { + stream.write(s, static_cast(length)); + } - @note This function is required to resolve an ambiguous overload error, - because pairs like `{"key", "value"}` can be both interpreted as - `object_t::value_type` or `std::initializer_list`, see - https://github.com/nlohmann/json/issues/235 for more information. + private: + std::basic_ostream& stream; + }; - @liveexample{The example shows how initializer lists are treated as - objects when possible.,push_back__initializer_list} - */ - void push_back(std::initializer_list init) + /// output adapter for basic_string + template + class output_string_adapter : public output_adapter { - if (is_object() and init.size() == 2 and init.begin()->is_string()) + public: + output_string_adapter(std::string& s) + : str(s) + {} + + void write_character(CharType c) override { - const string_t key = *init.begin(); - push_back(typename object_t::value_type(key, *(init.begin() + 1))); + str.push_back(c); } - else + + void write_characters(const CharType* s, size_t length) override { - push_back(basic_json(init)); + str.append(s, length); } - } + private: + std::basic_string& str; + }; + + + /////////////////// + // serialization // + /////////////////// + + /// @name serialization + /// @{ + + private: /*! - @brief add an object to an object - @copydoc push_back(std::initializer_list) + @brief wrapper around the serialization functions */ - reference operator+=(std::initializer_list init) + class serializer { - push_back(init); - return *this; - } + private: + serializer(const serializer&) = delete; + serializer& operator=(const serializer&) = delete; - /*! - @brief inserts element + public: + /*! + @param[in] s output stream to serialize to + @param[in] ichar indentation character to use + */ + serializer(output_adapter_t s, const char ichar) + : o(s), loc(std::localeconv()), + thousands_sep(!loc->thousands_sep ? '\0' : loc->thousands_sep[0]), + decimal_point(!loc->decimal_point ? '\0' : loc->decimal_point[0]), + indent_char(ichar), indent_string(512, indent_char) + {} - Inserts element @a val before iterator @a pos. + /*! + @brief internal implementation of the serialization function - @param[in] pos iterator before which the content will be inserted; may be - the end() iterator - @param[in] val element to insert - @return iterator pointing to the inserted @a val. + This function is called by the public member function dump and + organizes the serialization internally. The indentation level is + propagated as additional parameter. In case of arrays and objects, the + function is called recursively. - @throw std::domain_error if called on JSON values other than arrays; - example: `"cannot use insert() with string"` - @throw std::domain_error if @a pos is not an iterator of *this; example: - `"iterator does not fit current value"` + - strings and object keys are escaped using `escape_string()` + - integer numbers are converted implicitly via `operator<<` + - floating-point numbers are converted to a string using `"%g"` format + + @param[in] val value to serialize + @param[in] pretty_print whether the output shall be pretty-printed + @param[in] indent_step the indent level + @param[in] current_indent the current indent level (only used internally) + */ + void dump(const basic_json& val, + const bool pretty_print, + const unsigned int indent_step, + const unsigned int current_indent = 0) + { + switch (val.m_type) + { + case value_t::object: + { + if (val.m_value.object->empty()) + { + o->write_characters("{}", 2); + return; + } + + if (pretty_print) + { + o->write_characters("{\n", 2); + + // variable to hold indentation for recursive calls + const auto new_indent = current_indent + indent_step; + if (indent_string.size() < new_indent) + { + indent_string.resize(new_indent, ' '); + } + + // first n-1 elements + auto i = val.m_value.object->cbegin(); + for (size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i) + { + o->write_characters(indent_string.c_str(), new_indent); + o->write_character('\"'); + dump_escaped(i->first); + o->write_characters("\": ", 3); + dump(i->second, true, indent_step, new_indent); + o->write_characters(",\n", 2); + } + + // last element + assert(i != val.m_value.object->cend()); + o->write_characters(indent_string.c_str(), new_indent); + o->write_character('\"'); + dump_escaped(i->first); + o->write_characters("\": ", 3); + dump(i->second, true, indent_step, new_indent); + + o->write_character('\n'); + o->write_characters(indent_string.c_str(), current_indent); + o->write_character('}'); + } + else + { + o->write_character('{'); + + // first n-1 elements + auto i = val.m_value.object->cbegin(); + for (size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i) + { + o->write_character('\"'); + dump_escaped(i->first); + o->write_characters("\":", 2); + dump(i->second, false, indent_step, current_indent); + o->write_character(','); + } + + // last element + assert(i != val.m_value.object->cend()); + o->write_character('\"'); + dump_escaped(i->first); + o->write_characters("\":", 2); + dump(i->second, false, indent_step, current_indent); + + o->write_character('}'); + } + + return; + } + + case value_t::array: + { + if (val.m_value.array->empty()) + { + o->write_characters("[]", 2); + return; + } + + if (pretty_print) + { + o->write_characters("[\n", 2); + + // variable to hold indentation for recursive calls + const auto new_indent = current_indent + indent_step; + if (indent_string.size() < new_indent) + { + indent_string.resize(new_indent, ' '); + } + + // first n-1 elements + for (auto i = val.m_value.array->cbegin(); i != val.m_value.array->cend() - 1; ++i) + { + o->write_characters(indent_string.c_str(), new_indent); + dump(*i, true, indent_step, new_indent); + o->write_characters(",\n", 2); + } + + // last element + assert(not val.m_value.array->empty()); + o->write_characters(indent_string.c_str(), new_indent); + dump(val.m_value.array->back(), true, indent_step, new_indent); + + o->write_character('\n'); + o->write_characters(indent_string.c_str(), current_indent); + o->write_character(']'); + } + else + { + o->write_character('['); + + // first n-1 elements + for (auto i = val.m_value.array->cbegin(); i != val.m_value.array->cend() - 1; ++i) + { + dump(*i, false, indent_step, current_indent); + o->write_character(','); + } + + // last element + assert(not val.m_value.array->empty()); + dump(val.m_value.array->back(), false, indent_step, current_indent); - @complexity Constant plus linear in the distance between pos and end of the - container. + o->write_character(']'); + } + + return; + } + + case value_t::string: + { + o->write_character('\"'); + dump_escaped(*val.m_value.string); + o->write_character('\"'); + return; + } + + case value_t::boolean: + { + if (val.m_value.boolean) + { + o->write_characters("true", 4); + } + else + { + o->write_characters("false", 5); + } + return; + } + + case value_t::number_integer: + { + dump_integer(val.m_value.number_integer); + return; + } + + case value_t::number_unsigned: + { + dump_integer(val.m_value.number_unsigned); + return; + } + + case value_t::number_float: + { + dump_float(val.m_value.number_float); + return; + } - @liveexample{The example shows how `insert()` is used.,insert} + case value_t::discarded: + { + o->write_characters("", 11); + return; + } - @since version 1.0.0 - */ - iterator insert(const_iterator pos, const basic_json& val) - { - // insert only works for arrays - if (is_array()) - { - // check if iterator pos fits to this JSON value - if (pos.m_object != this) - { - throw std::domain_error("iterator does not fit current value"); + case value_t::null: + { + o->write_characters("null", 4); + return; + } } - - // insert to array and return iterator - iterator result(this); - result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, val); - return result; - } - else - { - throw std::domain_error("cannot use insert() with " + type_name()); } - } - /*! - @brief inserts element - @copydoc insert(const_iterator, const basic_json&) - */ - iterator insert(const_iterator pos, basic_json&& val) - { - return insert(pos, val); - } + private: + /*! + @brief calculates the extra space to escape a JSON string - /*! - @brief inserts elements + @param[in] s the string to escape + @return the number of characters required to escape string @a s - Inserts @a cnt copies of @a val before iterator @a pos. + @complexity Linear in the length of string @a s. + */ + static std::size_t extra_space(const string_t& s) noexcept + { + return std::accumulate(s.begin(), s.end(), size_t{}, + [](size_t res, typename string_t::value_type c) + { + switch (c) + { + case '"': + case '\\': + case '\b': + case '\f': + case '\n': + case '\r': + case '\t': + { + // from c (1 byte) to \x (2 bytes) + return res + 1; + } + + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x0b: + case 0x0e: + case 0x0f: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + case 0x18: + case 0x19: + case 0x1a: + case 0x1b: + case 0x1c: + case 0x1d: + case 0x1e: + case 0x1f: + { + // from c (1 byte) to \uxxxx (6 bytes) + return res + 5; + } - @param[in] pos iterator before which the content will be inserted; may be - the end() iterator - @param[in] cnt number of copies of @a val to insert - @param[in] val element to insert - @return iterator pointing to the first element inserted, or @a pos if - `cnt==0` + default: + { + return res; + } + } + }); + } - @throw std::domain_error if called on JSON values other than arrays; - example: `"cannot use insert() with string"` - @throw std::domain_error if @a pos is not an iterator of *this; example: - `"iterator does not fit current value"` + /*! + @brief dump escaped string - @complexity Linear in @a cnt plus linear in the distance between @a pos - and end of the container. + Escape a string by replacing certain special characters by a sequence + of an escape character (backslash) and another character and other + control characters by a sequence of "\u" followed by a four-digit hex + representation. The escaped string is written to output stream @a o. - @liveexample{The example shows how `insert()` is used.,insert__count} + @param[in] s the string to escape - @since version 1.0.0 - */ - iterator insert(const_iterator pos, size_type cnt, const basic_json& val) - { - // insert only works for arrays - if (is_array()) + @complexity Linear in the length of string @a s. + */ + void dump_escaped(const string_t& s) const { - // check if iterator pos fits to this JSON value - if (pos.m_object != this) + const auto space = extra_space(s); + if (space == 0) { - throw std::domain_error("iterator does not fit current value"); + o->write_characters(s.c_str(), s.size()); + return; } - // insert to array and return iterator - iterator result(this); - result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, cnt, val); - return result; - } - else - { - throw std::domain_error("cannot use insert() with " + type_name()); - } - } - - /*! - @brief inserts elements + // create a result string of necessary size + string_t result(s.size() + space, '\\'); + std::size_t pos = 0; - Inserts elements from range `[first, last)` before iterator @a pos. + for (const auto& c : s) + { + switch (c) + { + // quotation mark (0x22) + case '"': + { + result[pos + 1] = '"'; + pos += 2; + break; + } - @param[in] pos iterator before which the content will be inserted; may be - the end() iterator - @param[in] first begin of the range of elements to insert - @param[in] last end of the range of elements to insert + // reverse solidus (0x5c) + case '\\': + { + // nothing to change + pos += 2; + break; + } - @throw std::domain_error if called on JSON values other than arrays; - example: `"cannot use insert() with string"` - @throw std::domain_error if @a pos is not an iterator of *this; example: - `"iterator does not fit current value"` - @throw std::domain_error if @a first and @a last do not belong to the same - JSON value; example: `"iterators do not fit"` - @throw std::domain_error if @a first or @a last are iterators into - container for which insert is called; example: `"passed iterators may not - belong to container"` + // backspace (0x08) + case '\b': + { + result[pos + 1] = 'b'; + pos += 2; + break; + } - @return iterator pointing to the first element inserted, or @a pos if - `first==last` + // formfeed (0x0c) + case '\f': + { + result[pos + 1] = 'f'; + pos += 2; + break; + } - @complexity Linear in `std::distance(first, last)` plus linear in the - distance between @a pos and end of the container. + // newline (0x0a) + case '\n': + { + result[pos + 1] = 'n'; + pos += 2; + break; + } - @liveexample{The example shows how `insert()` is used.,insert__range} + // carriage return (0x0d) + case '\r': + { + result[pos + 1] = 'r'; + pos += 2; + break; + } - @since version 1.0.0 - */ - iterator insert(const_iterator pos, const_iterator first, const_iterator last) - { - // insert only works for arrays - if (not is_array()) - { - throw std::domain_error("cannot use insert() with " + type_name()); - } + // horizontal tab (0x09) + case '\t': + { + result[pos + 1] = 't'; + pos += 2; + break; + } - // check if iterator pos fits to this JSON value - if (pos.m_object != this) - { - throw std::domain_error("iterator does not fit current value"); - } + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x0b: + case 0x0e: + case 0x0f: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + case 0x18: + case 0x19: + case 0x1a: + case 0x1b: + case 0x1c: + case 0x1d: + case 0x1e: + case 0x1f: + { + // convert a number 0..15 to its hex representation + // (0..f) + static const char hexify[16] = + { + '0', '1', '2', '3', '4', '5', '6', '7', + '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' + }; - // check if range iterators belong to the same JSON object - if (first.m_object != last.m_object) - { - throw std::domain_error("iterators do not fit"); - } + // print character c as \uxxxx + for (const char m : + { 'u', '0', '0', hexify[c >> 4], hexify[c & 0x0f] + }) + { + result[++pos] = m; + } - if (first.m_object == this or last.m_object == this) - { - throw std::domain_error("passed iterators may not belong to container"); - } + ++pos; + break; + } - // insert to array and return iterator - iterator result(this); - result.m_it.array_iterator = m_value.array->insert( - pos.m_it.array_iterator, - first.m_it.array_iterator, - last.m_it.array_iterator); - return result; - } + default: + { + // all other characters are added as-is + result[pos++] = c; + break; + } + } + } - /*! - @brief inserts elements + assert(pos == s.size() + space); + o->write_characters(result.c_str(), result.size()); + } - Inserts elements from initializer list @a ilist before iterator @a pos. + /*! + @brief dump an integer - @param[in] pos iterator before which the content will be inserted; may be - the end() iterator - @param[in] ilist initializer list to insert the values from + Dump a given integer to output stream @a o. Works internally with + @a number_buffer. - @throw std::domain_error if called on JSON values other than arrays; - example: `"cannot use insert() with string"` - @throw std::domain_error if @a pos is not an iterator of *this; example: - `"iterator does not fit current value"` + @param[in] x integer number (signed or unsigned) to dump + @tparam NumberType either @a number_integer_t or @a number_unsigned_t + */ + template::value or + std::is_same::value, int> = 0> + void dump_integer(NumberType x) + { + // special case for "0" + if (x == 0) + { + o->write_character('0'); + return; + } - @return iterator pointing to the first element inserted, or @a pos if - `ilist` is empty + const bool is_negative = x < 0; + size_t i = 0; - @complexity Linear in `ilist.size()` plus linear in the distance between - @a pos and end of the container. + // spare 1 byte for '\0' + while (x != 0 and i < number_buffer.size() - 1) + { + const auto digit = std::labs(static_cast(x % 10)); + number_buffer[i++] = static_cast('0' + digit); + x /= 10; + } - @liveexample{The example shows how `insert()` is used.,insert__ilist} + // make sure the number has been processed completely + assert(x == 0); - @since version 1.0.0 - */ - iterator insert(const_iterator pos, std::initializer_list ilist) - { - // insert only works for arrays - if (not is_array()) - { - throw std::domain_error("cannot use insert() with " + type_name()); - } + if (is_negative) + { + // make sure there is capacity for the '-' + assert(i < number_buffer.size() - 2); + number_buffer[i++] = '-'; + } - // check if iterator pos fits to this JSON value - if (pos.m_object != this) - { - throw std::domain_error("iterator does not fit current value"); + std::reverse(number_buffer.begin(), number_buffer.begin() + i); + o->write_characters(number_buffer.data(), i); } - // insert to array and return iterator - iterator result(this); - result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, ilist); - return result; - } - - /*! - @brief exchanges the values - - Exchanges the contents of the JSON value with those of @a other. Does not - invoke any move, copy, or swap operations on individual elements. All - iterators and references remain valid. The past-the-end iterator is - invalidated. + /*! + @brief dump a floating-point number - @param[in,out] other JSON value to exchange the contents with + Dump a given floating-point number to output stream @a o. Works + internally with @a number_buffer. - @complexity Constant. + @param[in] x floating-point number to dump + */ + void dump_float(number_float_t x) + { + // NaN / inf + if (not std::isfinite(x) or std::isnan(x)) + { + o->write_characters("null", 4); + return; + } - @liveexample{The example below shows how JSON values can be swapped with - `swap()`.,swap__reference} + // special case for 0.0 and -0.0 + if (x == 0) + { + if (std::signbit(x)) + { + o->write_characters("-0.0", 4); + } + else + { + o->write_characters("0.0", 3); + } + return; + } - @since version 1.0.0 - */ - void swap(reference other) noexcept ( - std::is_nothrow_move_constructible::value and - std::is_nothrow_move_assignable::value and - std::is_nothrow_move_constructible::value and - std::is_nothrow_move_assignable::value - ) - { - std::swap(m_type, other.m_type); - std::swap(m_value, other.m_value); - assert_invariant(); - } + // get number of digits for a text -> float -> text round-trip + static constexpr auto d = std::numeric_limits::digits10; - /*! - @brief exchanges the values + // the actual conversion + std::ptrdiff_t len = snprintf(number_buffer.data(), number_buffer.size(), + "%.*g", d, x); - Exchanges the contents of a JSON array with those of @a other. Does not - invoke any move, copy, or swap operations on individual elements. All - iterators and references remain valid. The past-the-end iterator is - invalidated. + // negative value indicates an error + assert(len > 0); + // check if buffer was large enough + assert(static_cast(len) < number_buffer.size()); - @param[in,out] other array to exchange the contents with + // erase thousands separator + if (thousands_sep != '\0') + { + const auto end = std::remove(number_buffer.begin(), + number_buffer.begin() + len, + thousands_sep); + std::fill(end, number_buffer.end(), '\0'); + assert((end - number_buffer.begin()) <= len); + len = (end - number_buffer.begin()); + } - @throw std::domain_error when JSON value is not an array; example: `"cannot - use swap() with string"` + // convert decimal point to '.' + if (decimal_point != '\0' and decimal_point != '.') + { + for (auto& c : number_buffer) + { + if (c == decimal_point) + { + c = '.'; + break; + } + } + } - @complexity Constant. + o->write_characters(number_buffer.data(), static_cast(len)); - @liveexample{The example below shows how arrays can be swapped with - `swap()`.,swap__array_t} + // determine if need to append ".0" + const bool value_is_int_like = std::none_of(number_buffer.begin(), + number_buffer.begin() + len + 1, + [](char c) + { + return c == '.' or c == 'e'; + }); - @since version 1.0.0 - */ - void swap(array_t& other) - { - // swap only works for arrays - if (is_array()) - { - std::swap(*(m_value.array), other); - } - else - { - throw std::domain_error("cannot use swap() with " + type_name()); + if (value_is_int_like) + { + o->write_characters(".0", 2); + } } - } - /*! - @brief exchanges the values + private: + /// the output of the serializer + output_adapter_t o = nullptr; - Exchanges the contents of a JSON object with those of @a other. Does not - invoke any move, copy, or swap operations on individual elements. All - iterators and references remain valid. The past-the-end iterator is - invalidated. + /// a (hopefully) large enough character buffer + std::array number_buffer{{}}; - @param[in,out] other object to exchange the contents with + /// the locale + const std::lconv* loc = nullptr; + /// the locale's thousand separator character + const char thousands_sep = '\0'; + /// the locale's decimal point character + const char decimal_point = '\0'; - @throw std::domain_error when JSON value is not an object; example: - `"cannot use swap() with string"` + /// the indentation character + const char indent_char; - @complexity Constant. + /// the indentation string + string_t indent_string; + }; - @liveexample{The example below shows how objects can be swapped with - `swap()`.,swap__object_t} + public: + /*! + @brief serialize to stream - @since version 1.0.0 - */ - void swap(object_t& other) - { - // swap only works for objects - if (is_object()) - { - std::swap(*(m_value.object), other); - } - else - { - throw std::domain_error("cannot use swap() with " + type_name()); - } - } + Serialize the given JSON value @a j to the output stream @a o. The JSON + value will be serialized using the @ref dump member function. - /*! - @brief exchanges the values + - The indentation of the output can be controlled with the member variable + `width` of the output stream @a o. For instance, using the manipulator + `std::setw(4)` on @a o sets the indentation level to `4` and the + serialization result is the same as calling `dump(4)`. - Exchanges the contents of a JSON string with those of @a other. Does not - invoke any move, copy, or swap operations on individual elements. All - iterators and references remain valid. The past-the-end iterator is - invalidated. + - The indentation characrer can be controlled with the member variable + `fill` of the output stream @a o. For instance, the manipulator + `std::setfill('\\t')` sets indentation to use a tab character rather than + the default space character. - @param[in,out] other string to exchange the contents with + @param[in,out] o stream to serialize to + @param[in] j JSON value to serialize - @throw std::domain_error when JSON value is not a string; example: `"cannot - use swap() with boolean"` + @return the stream @a o - @complexity Constant. + @complexity Linear. - @liveexample{The example below shows how strings can be swapped with - `swap()`.,swap__string_t} + @liveexample{The example below shows the serialization with different + parameters to `width` to adjust the indentation level.,operator_serialize} - @since version 1.0.0 + @since version 1.0.0; indentaction character added in version 3.0.0 */ - void swap(string_t& other) + friend std::ostream& operator<<(std::ostream& o, const basic_json& j) { - // swap only works for strings - if (is_string()) - { - std::swap(*(m_value.string), other); - } - else - { - throw std::domain_error("cannot use swap() with " + type_name()); - } + // read width member and use it as indentation parameter if nonzero + const bool pretty_print = (o.width() > 0); + const auto indentation = (pretty_print ? o.width() : 0); + + // reset width to 0 for subsequent calls to this stream + o.width(0); + + // do the actual serialization + serializer s(output_adapter::create(o), o.fill()); + s.dump(j, pretty_print, static_cast(indentation)); + return o; + } + + /*! + @brief serialize to stream + @deprecated This stream operator is deprecated and will be removed in a + future version of the library. Please use + @ref std::ostream& operator<<(std::ostream&, const basic_json&) + instead; that is, replace calls like `j >> o;` with `o << j;`. + */ + JSON_DEPRECATED + friend std::ostream& operator>>(const basic_json& j, std::ostream& o) + { + return o << j; } /// @} - ////////////////////////////////////////// - // lexicographical comparison operators // - ////////////////////////////////////////// + ///////////////////// + // deserialization // + ///////////////////// - /// @name lexicographical comparison operators + /// @name deserialization /// @{ - private: /*! - @brief comparison operator for JSON types + @brief deserialize from an array - Returns an ordering that is similar to Python: - - order: null < boolean < number < object < array < string - - furthermore, each type is not smaller than itself + This function reads from an array of 1-byte values. - @since version 1.0.0 - */ - friend bool operator<(const value_t lhs, const value_t rhs) noexcept - { - static constexpr std::array order = {{ - 0, // null - 3, // object - 4, // array - 5, // string - 1, // boolean - 2, // integer - 2, // unsigned - 2, // float - } - }; + @pre Each element of the container has a size of 1 byte. Violating this + precondition yields undefined behavior. **This precondition is enforced + with a static assertion.** - // discarded values are not comparable - if (lhs == value_t::discarded or rhs == value_t::discarded) - { - return false; - } + @param[in] array array to read from + @param[in] cb a parser callback function of type @ref parser_callback_t + which is used to control the deserialization by filtering unwanted values + (optional) + + @return result of the deserialization + + @throw parse_error.101 if a parse error occurs; example: `""unexpected end + of input; expected string literal""` + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + + @complexity Linear in the length of the input. The parser is a predictive + LL(1) parser. The complexity can be higher if the parser callback function + @a cb has a super-linear complexity. + + @note A UTF-8 byte order mark is silently ignored. - return order[static_cast(lhs)] < order[static_cast(rhs)]; + @liveexample{The example below demonstrates the `parse()` function reading + from an array.,parse__array__parser_callback_t} + + @since version 2.0.3 + */ + template + static basic_json parse(T (&array)[N], + const parser_callback_t cb = nullptr) + { + // delegate the call to the iterator-range parse overload + return parse(std::begin(array), std::end(array), cb); } - public: /*! - @brief comparison: equal + @brief deserialize from string literal - Compares two JSON values for equality according to the following rules: - - Two JSON values are equal if (1) they are from the same type and (2) - their stored values are the same. - - Integer and floating-point numbers are automatically converted before - comparison. Floating-point numbers are compared indirectly: two - floating-point numbers `f1` and `f2` are considered equal if neither - `f1 > f2` nor `f2 > f1` holds. - - Two JSON null values are equal. + @tparam CharT character/literal type with size of 1 byte + @param[in] s string literal to read a serialized JSON value from + @param[in] cb a parser callback function of type @ref parser_callback_t + which is used to control the deserialization by filtering unwanted values + (optional) - @param[in] lhs first JSON value to consider - @param[in] rhs second JSON value to consider - @return whether the values @a lhs and @a rhs are equal + @return result of the deserialization - @complexity Linear. + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails - @liveexample{The example demonstrates comparing several JSON - types.,operator__equal} + @complexity Linear in the length of the input. The parser is a predictive + LL(1) parser. The complexity can be higher if the parser callback function + @a cb has a super-linear complexity. - @since version 1.0.0 - */ - friend bool operator==(const_reference lhs, const_reference rhs) noexcept - { - const auto lhs_type = lhs.type(); - const auto rhs_type = rhs.type(); + @note A UTF-8 byte order mark is silently ignored. + @note String containers like `std::string` or @ref string_t can be parsed + with @ref parse(const ContiguousContainer&, const parser_callback_t) - if (lhs_type == rhs_type) - { - switch (lhs_type) - { - case value_t::array: - { - return *lhs.m_value.array == *rhs.m_value.array; - } - case value_t::object: - { - return *lhs.m_value.object == *rhs.m_value.object; - } - case value_t::null: - { - return true; - } - case value_t::string: - { - return *lhs.m_value.string == *rhs.m_value.string; - } - case value_t::boolean: - { - return lhs.m_value.boolean == rhs.m_value.boolean; - } - case value_t::number_integer: - { - return lhs.m_value.number_integer == rhs.m_value.number_integer; - } - case value_t::number_unsigned: - { - return lhs.m_value.number_unsigned == rhs.m_value.number_unsigned; - } - case value_t::number_float: - { - return lhs.m_value.number_float == rhs.m_value.number_float; - } - default: - { - return false; - } - } - } - else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float) - { - return static_cast(lhs.m_value.number_integer) == rhs.m_value.number_float; - } - else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer) - { - return lhs.m_value.number_float == static_cast(rhs.m_value.number_integer); - } - else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float) - { - return static_cast(lhs.m_value.number_unsigned) == rhs.m_value.number_float; - } - else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned) - { - return lhs.m_value.number_float == static_cast(rhs.m_value.number_unsigned); - } - else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer) - { - return static_cast(lhs.m_value.number_unsigned) == rhs.m_value.number_integer; - } - else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned) - { - return lhs.m_value.number_integer == static_cast(rhs.m_value.number_unsigned); - } + @liveexample{The example below demonstrates the `parse()` function with + and without callback function.,parse__string__parser_callback_t} - return false; + @sa @ref parse(std::istream&, const parser_callback_t) for a version that + reads from an input stream + + @since version 1.0.0 (originally for @ref string_t) + */ + template::value and + std::is_integral::type>::value and + sizeof(typename std::remove_pointer::type) == 1, int>::type = 0> + static basic_json parse(const CharT s, + const parser_callback_t cb = nullptr) + { + return parser(input_adapter::create(s), cb).parse(true); } /*! - @brief comparison: equal + @brief deserialize from stream - The functions compares the given JSON value against a null pointer. As the - null pointer can be used to initialize a JSON value to null, a comparison - of JSON value @a v with a null pointer should be equivalent to call - `v.is_null()`. + @param[in,out] i stream to read a serialized JSON value from + @param[in] cb a parser callback function of type @ref parser_callback_t + which is used to control the deserialization by filtering unwanted values + (optional) - @param[in] v JSON value to consider - @return whether @a v is null + @return result of the deserialization - @complexity Constant. + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + @throw parse_error.111 if input stream is in a bad state - @liveexample{The example compares several JSON types to the null pointer. - ,operator__equal__nullptr_t} + @complexity Linear in the length of the input. The parser is a predictive + LL(1) parser. The complexity can be higher if the parser callback function + @a cb has a super-linear complexity. + + @note A UTF-8 byte order mark is silently ignored. + + @liveexample{The example below demonstrates the `parse()` function with + and without callback function.,parse__istream__parser_callback_t} + + @sa @ref parse(const CharT, const parser_callback_t) for a version + that reads from a string @since version 1.0.0 */ - friend bool operator==(const_reference v, std::nullptr_t) noexcept + static basic_json parse(std::istream& i, + const parser_callback_t cb = nullptr) { - return v.is_null(); + return parser(input_adapter::create(i), cb).parse(true); } /*! - @brief comparison: equal - @copydoc operator==(const_reference, std::nullptr_t) + @copydoc parse(std::istream&, const parser_callback_t) */ - friend bool operator==(std::nullptr_t, const_reference v) noexcept + static basic_json parse(std::istream&& i, + const parser_callback_t cb = nullptr) { - return v.is_null(); + return parser(input_adapter::create(i), cb).parse(true); } /*! - @brief comparison: not equal + @brief deserialize from an iterator range with contiguous storage - Compares two JSON values for inequality by calculating `not (lhs == rhs)`. + This function reads from an iterator range of a container with contiguous + storage of 1-byte values. Compatible container types include + `std::vector`, `std::string`, `std::array`, `std::valarray`, and + `std::initializer_list`. Furthermore, C-style arrays can be used with + `std::begin()`/`std::end()`. User-defined containers can be used as long + as they implement random-access iterators and a contiguous storage. - @param[in] lhs first JSON value to consider - @param[in] rhs second JSON value to consider - @return whether the values @a lhs and @a rhs are not equal + @pre The iterator range is contiguous. Violating this precondition yields + undefined behavior. **This precondition is enforced with an assertion.** + @pre Each element in the range has a size of 1 byte. Violating this + precondition yields undefined behavior. **This precondition is enforced + with a static assertion.** - @complexity Linear. + @warning There is no way to enforce all preconditions at compile-time. If + the function is called with noncompliant iterators and with + assertions switched off, the behavior is undefined and will most + likely yield segmentation violation. - @liveexample{The example demonstrates comparing several JSON - types.,operator__notequal} + @tparam IteratorType iterator of container with contiguous storage + @param[in] first begin of the range to parse (included) + @param[in] last end of the range to parse (excluded) + @param[in] cb a parser callback function of type @ref parser_callback_t + which is used to control the deserialization by filtering unwanted values + (optional) - @since version 1.0.0 + @return result of the deserialization + + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + + @complexity Linear in the length of the input. The parser is a predictive + LL(1) parser. The complexity can be higher if the parser callback function + @a cb has a super-linear complexity. + + @note A UTF-8 byte order mark is silently ignored. + + @liveexample{The example below demonstrates the `parse()` function reading + from an iterator range.,parse__iteratortype__parser_callback_t} + + @since version 2.0.3 */ - friend bool operator!=(const_reference lhs, const_reference rhs) noexcept + template::iterator_category>::value, int>::type = 0> + static basic_json parse(IteratorType first, IteratorType last, + const parser_callback_t cb = nullptr) { - return not (lhs == rhs); + return parser(input_adapter::create(first, last), cb).parse(true); } /*! - @brief comparison: not equal + @brief deserialize from a container with contiguous storage + + This function reads from a container with contiguous storage of 1-byte + values. Compatible container types include `std::vector`, `std::string`, + `std::array`, and `std::initializer_list`. User-defined containers can be + used as long as they implement random-access iterators and a contiguous + storage. + + @pre The container storage is contiguous. Violating this precondition + yields undefined behavior. **This precondition is enforced with an + assertion.** + @pre Each element of the container has a size of 1 byte. Violating this + precondition yields undefined behavior. **This precondition is enforced + with a static assertion.** - The functions compares the given JSON value against a null pointer. As the - null pointer can be used to initialize a JSON value to null, a comparison - of JSON value @a v with a null pointer should be equivalent to call - `not v.is_null()`. + @warning There is no way to enforce all preconditions at compile-time. If + the function is called with a noncompliant container and with + assertions switched off, the behavior is undefined and will most + likely yield segmentation violation. - @param[in] v JSON value to consider - @return whether @a v is not null + @tparam ContiguousContainer container type with contiguous storage + @param[in] c container to read from + @param[in] cb a parser callback function of type @ref parser_callback_t + which is used to control the deserialization by filtering unwanted values + (optional) - @complexity Constant. + @return result of the deserialization - @liveexample{The example compares several JSON types to the null pointer. - ,operator__notequal__nullptr_t} + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails - @since version 1.0.0 + @complexity Linear in the length of the input. The parser is a predictive + LL(1) parser. The complexity can be higher if the parser callback function + @a cb has a super-linear complexity. + + @note A UTF-8 byte order mark is silently ignored. + + @liveexample{The example below demonstrates the `parse()` function reading + from a contiguous container.,parse__contiguouscontainer__parser_callback_t} + + @since version 2.0.3 */ - friend bool operator!=(const_reference v, std::nullptr_t) noexcept + template::value and + std::is_base_of< + std::random_access_iterator_tag, + typename std::iterator_traits()))>::iterator_category>::value + , int>::type = 0> + static basic_json parse(const ContiguousContainer& c, + const parser_callback_t cb = nullptr) { - return not v.is_null(); + // delegate the call to the iterator-range parse overload + return parse(std::begin(c), std::end(c), cb); } /*! - @brief comparison: not equal - @copydoc operator!=(const_reference, std::nullptr_t) + @brief deserialize from stream + @deprecated This stream operator is deprecated and will be removed in a + future version of the library. Please use + @ref std::istream& operator>>(std::istream&, basic_json&) + instead; that is, replace calls like `j << i;` with `i >> j;`. */ - friend bool operator!=(std::nullptr_t, const_reference v) noexcept + JSON_DEPRECATED + friend std::istream& operator<<(basic_json& j, std::istream& i) { - return not v.is_null(); + j = parser(input_adapter::create(i)).parse(false); + return i; } /*! - @brief comparison: less than + @brief deserialize from stream - Compares whether one JSON value @a lhs is less than another JSON value @a - rhs according to the following rules: - - If @a lhs and @a rhs have the same type, the values are compared using - the default `<` operator. - - Integer and floating-point numbers are automatically converted before - comparison - - In case @a lhs and @a rhs have different types, the values are ignored - and the order of the types is considered, see - @ref operator<(const value_t, const value_t). + Deserializes an input stream to a JSON value. - @param[in] lhs first JSON value to consider - @param[in] rhs second JSON value to consider - @return whether @a lhs is less than @a rhs + @param[in,out] i input stream to read a serialized JSON value from + @param[in,out] j JSON value to write the deserialized input to - @complexity Linear. + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + @throw parse_error.111 if input stream is in a bad state - @liveexample{The example demonstrates comparing several JSON - types.,operator__less} + @complexity Linear in the length of the input. The parser is a predictive + LL(1) parser. + + @note A UTF-8 byte order mark is silently ignored. + + @liveexample{The example below shows how a JSON value is constructed by + reading a serialization from a stream.,operator_deserialize} + + @sa parse(std::istream&, const parser_callback_t) for a variant with a + parser callback function to filter values while parsing @since version 1.0.0 */ - friend bool operator<(const_reference lhs, const_reference rhs) noexcept + friend std::istream& operator>>(std::istream& i, basic_json& j) { - const auto lhs_type = lhs.type(); - const auto rhs_type = rhs.type(); + j = parser(input_adapter::create(i)).parse(false); + return i; + } - if (lhs_type == rhs_type) - { - switch (lhs_type) - { - case value_t::array: - { - return *lhs.m_value.array < *rhs.m_value.array; - } - case value_t::object: - { - return *lhs.m_value.object < *rhs.m_value.object; - } - case value_t::null: - { - return false; - } - case value_t::string: - { - return *lhs.m_value.string < *rhs.m_value.string; - } - case value_t::boolean: - { - return lhs.m_value.boolean < rhs.m_value.boolean; - } - case value_t::number_integer: - { - return lhs.m_value.number_integer < rhs.m_value.number_integer; - } - case value_t::number_unsigned: - { - return lhs.m_value.number_unsigned < rhs.m_value.number_unsigned; - } - case value_t::number_float: - { - return lhs.m_value.number_float < rhs.m_value.number_float; - } - default: - { - return false; - } - } - } - else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float) - { - return static_cast(lhs.m_value.number_integer) < rhs.m_value.number_float; - } - else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer) - { - return lhs.m_value.number_float < static_cast(rhs.m_value.number_integer); - } - else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float) - { - return static_cast(lhs.m_value.number_unsigned) < rhs.m_value.number_float; - } - else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned) - { - return lhs.m_value.number_float < static_cast(rhs.m_value.number_unsigned); - } - else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned) - { - return lhs.m_value.number_integer < static_cast(rhs.m_value.number_unsigned); - } - else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer) - { - return static_cast(lhs.m_value.number_unsigned) < rhs.m_value.number_integer; - } + /// @} - // We only reach this line if we cannot compare values. In that case, - // we compare types. Note we have to call the operator explicitly, - // because MSVC has problems otherwise. - return operator<(lhs_type, rhs_type); - } + /////////////////////////// + // convenience functions // + /////////////////////////// /*! - @brief comparison: less than or equal + @brief return the type as string - Compares whether one JSON value @a lhs is less than or equal to another - JSON value by calculating `not (rhs < lhs)`. + Returns the type name as string to be used in error messages - usually to + indicate that a function was called on a wrong JSON type. - @param[in] lhs first JSON value to consider - @param[in] rhs second JSON value to consider - @return whether @a lhs is less than or equal to @a rhs + @return basically a string representation of a the @a m_type member - @complexity Linear. + @complexity Constant. - @liveexample{The example demonstrates comparing several JSON - types.,operator__greater} + @liveexample{The following code exemplifies `type_name()` for all JSON + types.,type_name} - @since version 1.0.0 + @since version 1.0.0, public since 2.1.0 */ - friend bool operator<=(const_reference lhs, const_reference rhs) noexcept + std::string type_name() const { - return not (rhs < lhs); + { + switch (m_type) + { + case value_t::null: + return "null"; + case value_t::object: + return "object"; + case value_t::array: + return "array"; + case value_t::string: + return "string"; + case value_t::boolean: + return "boolean"; + case value_t::discarded: + return "discarded"; + default: + return "number"; + } + } } - /*! - @brief comparison: greater than - Compares whether one JSON value @a lhs is greater than another - JSON value by calculating `not (lhs <= rhs)`. + private: + ////////////////////// + // member variables // + ////////////////////// - @param[in] lhs first JSON value to consider - @param[in] rhs second JSON value to consider - @return whether @a lhs is greater than to @a rhs + /// the type of the current element + value_t m_type = value_t::null; - @complexity Linear. + /// the value of the current element + json_value m_value = {}; - @liveexample{The example demonstrates comparing several JSON - types.,operator__lessequal} - @since version 1.0.0 - */ - friend bool operator>(const_reference lhs, const_reference rhs) noexcept - { - return not (lhs <= rhs); - } + private: + /////////////// + // iterators // + /////////////// /*! - @brief comparison: greater than or equal + @brief an iterator for primitive JSON types - Compares whether one JSON value @a lhs is greater than or equal to another - JSON value by calculating `not (lhs < rhs)`. + This class models an iterator for primitive JSON types (boolean, number, + string). It's only purpose is to allow the iterator/const_iterator classes + to "iterate" over primitive values. Internally, the iterator is modeled by + a `difference_type` variable. Value begin_value (`0`) models the begin, + end_value (`1`) models past the end. + */ + class primitive_iterator_t + { + public: - @param[in] lhs first JSON value to consider - @param[in] rhs second JSON value to consider - @return whether @a lhs is greater than or equal to @a rhs + difference_type get_value() const noexcept + { + return m_it; + } + /// set iterator to a defined beginning + void set_begin() noexcept + { + m_it = begin_value; + } - @complexity Linear. + /// set iterator to a defined past the end + void set_end() noexcept + { + m_it = end_value; + } - @liveexample{The example demonstrates comparing several JSON - types.,operator__greaterequal} + /// return whether the iterator can be dereferenced + constexpr bool is_begin() const noexcept + { + return (m_it == begin_value); + } - @since version 1.0.0 - */ - friend bool operator>=(const_reference lhs, const_reference rhs) noexcept - { - return not (lhs < rhs); - } + /// return whether the iterator is at end + constexpr bool is_end() const noexcept + { + return (m_it == end_value); + } - /// @} + friend constexpr bool operator==(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it == rhs.m_it; + } + friend constexpr bool operator!=(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return !(lhs == rhs); + } - /////////////////// - // serialization // - /////////////////// + friend constexpr bool operator<(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it < rhs.m_it; + } - /// @name serialization - /// @{ + friend constexpr bool operator<=(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it <= rhs.m_it; + } - /*! - @brief serialize to stream + friend constexpr bool operator>(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it > rhs.m_it; + } - Serialize the given JSON value @a j to the output stream @a o. The JSON - value will be serialized using the @ref dump member function. The - indentation of the output can be controlled with the member variable - `width` of the output stream @a o. For instance, using the manipulator - `std::setw(4)` on @a o sets the indentation level to `4` and the - serialization result is the same as calling `dump(4)`. + friend constexpr bool operator>=(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it >= rhs.m_it; + } - @note During serializaion, the locale and the precision of the output - stream @a o are changed. The original values are restored when the - function returns. + primitive_iterator_t operator+(difference_type i) + { + auto result = *this; + result += i; + return result; + } - @param[in,out] o stream to serialize to - @param[in] j JSON value to serialize + friend constexpr difference_type operator-(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it - rhs.m_it; + } - @return the stream @a o + friend std::ostream& operator<<(std::ostream& os, primitive_iterator_t it) + { + return os << it.m_it; + } - @complexity Linear. + primitive_iterator_t& operator++() + { + ++m_it; + return *this; + } - @liveexample{The example below shows the serialization with different - parameters to `width` to adjust the indentation level.,operator_serialize} + primitive_iterator_t operator++(int) + { + auto result = *this; + m_it++; + return result; + } - @since version 1.0.0 - */ - friend std::ostream& operator<<(std::ostream& o, const basic_json& j) - { - // read width member and use it as indentation parameter if nonzero - const bool pretty_print = (o.width() > 0); - const auto indentation = (pretty_print ? o.width() : 0); + primitive_iterator_t& operator--() + { + --m_it; + return *this; + } - // reset width to 0 for subsequent calls to this stream - o.width(0); + primitive_iterator_t operator--(int) + { + auto result = *this; + m_it--; + return result; + } - // fix locale problems - const auto old_locale = o.imbue(std::locale::classic()); - // set precision + primitive_iterator_t& operator+=(difference_type n) + { + m_it += n; + return *this; + } - // 6, 15 or 16 digits of precision allows round-trip IEEE 754 - // string->float->string, string->double->string or string->long - // double->string; to be safe, we read this value from - // std::numeric_limits::digits10 - const auto old_precision = o.precision(std::numeric_limits::digits10); + primitive_iterator_t& operator-=(difference_type n) + { + m_it -= n; + return *this; + } - // do the actual serialization - j.dump(o, pretty_print, static_cast(indentation)); + private: + static constexpr difference_type begin_value = 0; + static constexpr difference_type end_value = begin_value + 1; - // reset locale and precision - o.imbue(old_locale); - o.precision(old_precision); - return o; - } + /// iterator as signed integer type + difference_type m_it = std::numeric_limits::denorm_min(); + }; /*! - @brief serialize to stream - @copydoc operator<<(std::ostream&, const basic_json&) + @brief an iterator value + + @note This structure could easily be a union, but MSVC currently does not + allow unions members with complex constructors, see + https://github.com/nlohmann/json/pull/105. */ - friend std::ostream& operator>>(const basic_json& j, std::ostream& o) + struct internal_iterator { - return o << j; - } + /// iterator for JSON objects + typename object_t::iterator object_iterator; + /// iterator for JSON arrays + typename array_t::iterator array_iterator; + /// generic iterator for all other types + primitive_iterator_t primitive_iterator; - /// @} + /// create an uninitialized internal_iterator + internal_iterator() noexcept + : object_iterator(), array_iterator(), primitive_iterator() + {} + }; + /// proxy class for the iterator_wrapper functions + template + class iteration_proxy + { + private: + /// helper class for iteration + class iteration_proxy_internal + { + private: + /// the iterator + IteratorType anchor; + /// an index for arrays (used to create key names) + size_t array_index = 0; - ///////////////////// - // deserialization // - ///////////////////// + public: + explicit iteration_proxy_internal(IteratorType it) noexcept + : anchor(it) + {} - /// @name deserialization - /// @{ + /// dereference operator (needed for range-based for) + iteration_proxy_internal& operator*() + { + return *this; + } - /*! - @brief deserialize from an array + /// increment operator (needed for range-based for) + iteration_proxy_internal& operator++() + { + ++anchor; + ++array_index; - This function reads from an array of 1-byte values. + return *this; + } - @pre Each element of the container has a size of 1 byte. Violating this - precondition yields undefined behavior. **This precondition is enforced - with a static assertion.** + /// inequality operator (needed for range-based for) + bool operator!= (const iteration_proxy_internal& o) const + { + return anchor != o.anchor; + } - @param[in] array array to read from - @param[in] cb a parser callback function of type @ref parser_callback_t - which is used to control the deserialization by filtering unwanted values - (optional) + /// return key of the iterator + typename basic_json::string_t key() const + { + assert(anchor.m_object != nullptr); - @return result of the deserialization + switch (anchor.m_object->type()) + { + // use integer array index as key + case value_t::array: + { + return std::to_string(array_index); + } - @complexity Linear in the length of the input. The parser is a predictive - LL(1) parser. The complexity can be higher if the parser callback function - @a cb has a super-linear complexity. + // use key from the object + case value_t::object: + { + return anchor.key(); + } - @note A UTF-8 byte order mark is silently ignored. + // use an empty key for all primitive types + default: + { + return ""; + } + } + } - @liveexample{The example below demonstrates the `parse()` function reading - from an array.,parse__array__parser_callback_t} + /// return value of the iterator + typename IteratorType::reference value() const + { + return anchor.value(); + } + }; - @since version 2.0.3 - */ - template - static basic_json parse(T (&array)[N], - const parser_callback_t cb = nullptr) - { - // delegate the call to the iterator-range parse overload - return parse(std::begin(array), std::end(array), cb); - } + /// the container to iterate + typename IteratorType::reference container; - /*! - @brief deserialize from string literal + public: + /// construct iteration proxy from a container + explicit iteration_proxy(typename IteratorType::reference cont) + : container(cont) + {} - @tparam CharT character/literal type with size of 1 byte - @param[in] s string literal to read a serialized JSON value from - @param[in] cb a parser callback function of type @ref parser_callback_t - which is used to control the deserialization by filtering unwanted values - (optional) + /// return iterator begin (needed for range-based for) + iteration_proxy_internal begin() noexcept + { + return iteration_proxy_internal(container.begin()); + } - @return result of the deserialization + /// return iterator end (needed for range-based for) + iteration_proxy_internal end() noexcept + { + return iteration_proxy_internal(container.end()); + } + }; - @complexity Linear in the length of the input. The parser is a predictive - LL(1) parser. The complexity can be higher if the parser callback function - @a cb has a super-linear complexity. + public: + /*! + @brief a template for a random access iterator for the @ref basic_json class - @note A UTF-8 byte order mark is silently ignored. - @note String containers like `std::string` or @ref string_t can be parsed - with @ref parse(const ContiguousContainer&, const parser_callback_t) + This class implements a both iterators (iterator and const_iterator) for the + @ref basic_json class. - @liveexample{The example below demonstrates the `parse()` function with - and without callback function.,parse__string__parser_callback_t} + @note An iterator is called *initialized* when a pointer to a JSON value + has been set (e.g., by a constructor or a copy assignment). If the + iterator is default-constructed, it is *uninitialized* and most + methods are undefined. **The library uses assertions to detect calls + on uninitialized iterators.** - @sa @ref parse(std::istream&, const parser_callback_t) for a version that - reads from an input stream + @requirement The class satisfies the following concept requirements: + - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator): + The iterator that can be moved to point (forward and backward) to any + element in constant time. - @since version 1.0.0 (originally for @ref string_t) + @since version 1.0.0, simplified in version 2.0.9 */ - template::value and - std::is_integral::type>::value and - sizeof(typename std::remove_pointer::type) == 1, int>::type = 0> - static basic_json parse(const CharPT s, - const parser_callback_t cb = nullptr) + template + class iter_impl : public std::iterator { - return parser(reinterpret_cast(s), cb).parse(); - } + /// allow basic_json to access private members + friend class basic_json; - /*! - @brief deserialize from stream + // make sure U is basic_json or const basic_json + static_assert(std::is_same::value + or std::is_same::value, + "iter_impl only accepts (const) basic_json"); - @param[in,out] i stream to read a serialized JSON value from - @param[in] cb a parser callback function of type @ref parser_callback_t - which is used to control the deserialization by filtering unwanted values - (optional) + public: + /// the type of the values when the iterator is dereferenced + using value_type = typename basic_json::value_type; + /// a type to represent differences between iterators + using difference_type = typename basic_json::difference_type; + /// defines a pointer to the type iterated over (value_type) + using pointer = typename std::conditional::value, + typename basic_json::const_pointer, + typename basic_json::pointer>::type; + /// defines a reference to the type iterated over (value_type) + using reference = typename std::conditional::value, + typename basic_json::const_reference, + typename basic_json::reference>::type; + /// the category of the iterator + using iterator_category = std::bidirectional_iterator_tag; - @return result of the deserialization + /// default constructor + iter_impl() = default; - @complexity Linear in the length of the input. The parser is a predictive - LL(1) parser. The complexity can be higher if the parser callback function - @a cb has a super-linear complexity. + /*! + @brief constructor for a given JSON instance + @param[in] object pointer to a JSON object for this iterator + @pre object != nullptr + @post The iterator is initialized; i.e. `m_object != nullptr`. + */ + explicit iter_impl(pointer object) noexcept + : m_object(object) + { + assert(m_object != nullptr); - @note A UTF-8 byte order mark is silently ignored. + switch (m_object->m_type) + { + case basic_json::value_t::object: + { + m_it.object_iterator = typename object_t::iterator(); + break; + } - @liveexample{The example below demonstrates the `parse()` function with - and without callback function.,parse__istream__parser_callback_t} + case basic_json::value_t::array: + { + m_it.array_iterator = typename array_t::iterator(); + break; + } - @sa @ref parse(const char*, const parser_callback_t) for a version - that reads from a string + default: + { + m_it.primitive_iterator = primitive_iterator_t(); + break; + } + } + } - @since version 1.0.0 - */ - static basic_json parse(std::istream& i, - const parser_callback_t cb = nullptr) - { - return parser(i, cb).parse(); - } + /* + Use operator `const_iterator` instead of `const_iterator(const iterator& + other) noexcept` to avoid two class definitions for @ref iterator and + @ref const_iterator. - /*! - @copydoc parse(std::istream&, const parser_callback_t) - */ - static basic_json parse(std::istream&& i, - const parser_callback_t cb = nullptr) - { - return parser(i, cb).parse(); - } + This function is only called if this class is an @ref iterator. If this + class is a @ref const_iterator this function is not called. + */ + operator const_iterator() const + { + const_iterator ret; - /*! - @brief deserialize from an iterator range with contiguous storage + if (m_object) + { + ret.m_object = m_object; + ret.m_it = m_it; + } - This function reads from an iterator range of a container with contiguous - storage of 1-byte values. Compatible container types include - `std::vector`, `std::string`, `std::array`, `std::valarray`, and - `std::initializer_list`. Furthermore, C-style arrays can be used with - `std::begin()`/`std::end()`. User-defined containers can be used as long - as they implement random-access iterators and a contiguous storage. + return ret; + } - @pre The iterator range is contiguous. Violating this precondition yields - undefined behavior. **This precondition is enforced with an assertion.** - @pre Each element in the range has a size of 1 byte. Violating this - precondition yields undefined behavior. **This precondition is enforced - with a static assertion.** + /*! + @brief copy constructor + @param[in] other iterator to copy from + @note It is not checked whether @a other is initialized. + */ + iter_impl(const iter_impl& other) noexcept + : m_object(other.m_object), m_it(other.m_it) + {} - @warning There is no way to enforce all preconditions at compile-time. If - the function is called with noncompliant iterators and with - assertions switched off, the behavior is undefined and will most - likely yield segmentation violation. + /*! + @brief copy assignment + @param[in,out] other iterator to copy from + @note It is not checked whether @a other is initialized. + */ + iter_impl& operator=(iter_impl other) noexcept( + std::is_nothrow_move_constructible::value and + std::is_nothrow_move_assignable::value and + std::is_nothrow_move_constructible::value and + std::is_nothrow_move_assignable::value + ) + { + std::swap(m_object, other.m_object); + std::swap(m_it, other.m_it); + return *this; + } - @tparam IteratorType iterator of container with contiguous storage - @param[in] first begin of the range to parse (included) - @param[in] last end of the range to parse (excluded) - @param[in] cb a parser callback function of type @ref parser_callback_t - which is used to control the deserialization by filtering unwanted values - (optional) + private: + /*! + @brief set the iterator to the first value + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + void set_begin() noexcept + { + assert(m_object != nullptr); - @return result of the deserialization + switch (m_object->m_type) + { + case basic_json::value_t::object: + { + m_it.object_iterator = m_object->m_value.object->begin(); + break; + } - @complexity Linear in the length of the input. The parser is a predictive - LL(1) parser. The complexity can be higher if the parser callback function - @a cb has a super-linear complexity. + case basic_json::value_t::array: + { + m_it.array_iterator = m_object->m_value.array->begin(); + break; + } - @note A UTF-8 byte order mark is silently ignored. + case basic_json::value_t::null: + { + // set to end so begin()==end() is true: null is empty + m_it.primitive_iterator.set_end(); + break; + } - @liveexample{The example below demonstrates the `parse()` function reading - from an iterator range.,parse__iteratortype__parser_callback_t} + default: + { + m_it.primitive_iterator.set_begin(); + break; + } + } + } - @since version 2.0.3 - */ - template::iterator_category>::value, int>::type = 0> - static basic_json parse(IteratorType first, IteratorType last, - const parser_callback_t cb = nullptr) - { - // assertion to check that the iterator range is indeed contiguous, - // see http://stackoverflow.com/a/35008842/266378 for more discussion - assert(std::accumulate(first, last, std::make_pair(true, 0), - [&first](std::pair res, decltype(*first) val) + /*! + @brief set the iterator past the last value + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + void set_end() noexcept { - res.first &= (val == *(std::next(std::addressof(*first), res.second++))); - return res; - }).first); + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case basic_json::value_t::object: + { + m_it.object_iterator = m_object->m_value.object->end(); + break; + } - // assertion to check that each element is 1 byte long - static_assert(sizeof(typename std::iterator_traits::value_type) == 1, - "each element in the iterator range must have the size of 1 byte"); + case basic_json::value_t::array: + { + m_it.array_iterator = m_object->m_value.array->end(); + break; + } - // if iterator range is empty, create a parser with an empty string - // to generate "unexpected EOF" error message - if (std::distance(first, last) <= 0) - { - return parser("").parse(); + default: + { + m_it.primitive_iterator.set_end(); + break; + } + } } - return parser(first, last, cb).parse(); - } + public: + /*! + @brief return a reference to the value pointed to by the iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + reference operator*() const + { + assert(m_object != nullptr); - /*! - @brief deserialize from a container with contiguous storage + switch (m_object->m_type) + { + case basic_json::value_t::object: + { + assert(m_it.object_iterator != m_object->m_value.object->end()); + return m_it.object_iterator->second; + } - This function reads from a container with contiguous storage of 1-byte - values. Compatible container types include `std::vector`, `std::string`, - `std::array`, and `std::initializer_list`. User-defined containers can be - used as long as they implement random-access iterators and a contiguous - storage. + case basic_json::value_t::array: + { + assert(m_it.array_iterator != m_object->m_value.array->end()); + return *m_it.array_iterator; + } - @pre The container storage is contiguous. Violating this precondition - yields undefined behavior. **This precondition is enforced with an - assertion.** - @pre Each element of the container has a size of 1 byte. Violating this - precondition yields undefined behavior. **This precondition is enforced - with a static assertion.** + case basic_json::value_t::null: + { + JSON_THROW(invalid_iterator::create(214, "cannot get value")); + } - @warning There is no way to enforce all preconditions at compile-time. If - the function is called with a noncompliant container and with - assertions switched off, the behavior is undefined and will most - likely yield segmentation violation. + default: + { + if (m_it.primitive_iterator.is_begin()) + { + return *m_object; + } - @tparam ContiguousContainer container type with contiguous storage - @param[in] c container to read from - @param[in] cb a parser callback function of type @ref parser_callback_t - which is used to control the deserialization by filtering unwanted values - (optional) + JSON_THROW(invalid_iterator::create(214, "cannot get value")); + } + } + } - @return result of the deserialization + /*! + @brief dereference the iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + pointer operator->() const + { + assert(m_object != nullptr); - @complexity Linear in the length of the input. The parser is a predictive - LL(1) parser. The complexity can be higher if the parser callback function - @a cb has a super-linear complexity. + switch (m_object->m_type) + { + case basic_json::value_t::object: + { + assert(m_it.object_iterator != m_object->m_value.object->end()); + return &(m_it.object_iterator->second); + } - @note A UTF-8 byte order mark is silently ignored. + case basic_json::value_t::array: + { + assert(m_it.array_iterator != m_object->m_value.array->end()); + return &*m_it.array_iterator; + } - @liveexample{The example below demonstrates the `parse()` function reading - from a contiguous container.,parse__contiguouscontainer__parser_callback_t} + default: + { + if (m_it.primitive_iterator.is_begin()) + { + return m_object; + } - @since version 2.0.3 - */ - template::value and - std::is_base_of< - std::random_access_iterator_tag, - typename std::iterator_traits()))>::iterator_category>::value - , int>::type = 0> - static basic_json parse(const ContiguousContainer& c, - const parser_callback_t cb = nullptr) - { - // delegate the call to the iterator-range parse overload - return parse(std::begin(c), std::end(c), cb); - } + JSON_THROW(invalid_iterator::create(214, "cannot get value")); + } + } + } - /*! - @brief deserialize from stream + /*! + @brief post-increment (it++) + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl operator++(int) + { + auto result = *this; + ++(*this); + return result; + } - Deserializes an input stream to a JSON value. + /*! + @brief pre-increment (++it) + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl& operator++() + { + assert(m_object != nullptr); - @param[in,out] i input stream to read a serialized JSON value from - @param[in,out] j JSON value to write the deserialized input to + switch (m_object->m_type) + { + case basic_json::value_t::object: + { + std::advance(m_it.object_iterator, 1); + break; + } - @throw std::invalid_argument in case of parse errors + case basic_json::value_t::array: + { + std::advance(m_it.array_iterator, 1); + break; + } - @complexity Linear in the length of the input. The parser is a predictive - LL(1) parser. + default: + { + ++m_it.primitive_iterator; + break; + } + } - @note A UTF-8 byte order mark is silently ignored. + return *this; + } - @liveexample{The example below shows how a JSON value is constructed by - reading a serialization from a stream.,operator_deserialize} + /*! + @brief post-decrement (it--) + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl operator--(int) + { + auto result = *this; + --(*this); + return result; + } - @sa parse(std::istream&, const parser_callback_t) for a variant with a - parser callback function to filter values while parsing + /*! + @brief pre-decrement (--it) + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl& operator--() + { + assert(m_object != nullptr); - @since version 1.0.0 - */ - friend std::istream& operator<<(basic_json& j, std::istream& i) - { - j = parser(i).parse(); - return i; - } + switch (m_object->m_type) + { + case basic_json::value_t::object: + { + std::advance(m_it.object_iterator, -1); + break; + } - /*! - @brief deserialize from stream - @copydoc operator<<(basic_json&, std::istream&) - */ - friend std::istream& operator>>(std::istream& i, basic_json& j) - { - j = parser(i).parse(); - return i; - } + case basic_json::value_t::array: + { + std::advance(m_it.array_iterator, -1); + break; + } - /// @} + default: + { + --m_it.primitive_iterator; + break; + } + } + return *this; + } - private: - /////////////////////////// - // convenience functions // - /////////////////////////// + /*! + @brief comparison: equal + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator==(const iter_impl& other) const + { + // if objects are not the same, the comparison is undefined + if (m_object != other.m_object) + { + JSON_THROW(invalid_iterator::create(212, "cannot compare iterators of different containers")); + } - /*! - @brief return the type as string + assert(m_object != nullptr); - Returns the type name as string to be used in error messages - usually to - indicate that a function was called on a wrong JSON type. + switch (m_object->m_type) + { + case basic_json::value_t::object: + { + return (m_it.object_iterator == other.m_it.object_iterator); + } - @return basically a string representation of a the @a m_type member + case basic_json::value_t::array: + { + return (m_it.array_iterator == other.m_it.array_iterator); + } - @complexity Constant. + default: + { + return (m_it.primitive_iterator == other.m_it.primitive_iterator); + } + } + } - @since version 1.0.0 - */ - std::string type_name() const - { - switch (m_type) + /*! + @brief comparison: not equal + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator!=(const iter_impl& other) const { - case value_t::null: - return "null"; - case value_t::object: - return "object"; - case value_t::array: - return "array"; - case value_t::string: - return "string"; - case value_t::boolean: - return "boolean"; - case value_t::discarded: - return "discarded"; - default: - return "number"; + return not operator==(other); } - } - /*! - @brief calculates the extra space to escape a JSON string + /*! + @brief comparison: smaller + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator<(const iter_impl& other) const + { + // if objects are not the same, the comparison is undefined + if (m_object != other.m_object) + { + JSON_THROW(invalid_iterator::create(212, "cannot compare iterators of different containers")); + } - @param[in] s the string to escape - @return the number of characters required to escape string @a s + assert(m_object != nullptr); - @complexity Linear in the length of string @a s. - */ - static std::size_t extra_space(const string_t& s) noexcept - { - return std::accumulate(s.begin(), s.end(), size_t{}, - [](size_t res, typename string_t::value_type c) - { - switch (c) + switch (m_object->m_type) { - case '"': - case '\\': - case '\b': - case '\f': - case '\n': - case '\r': - case '\t': + case basic_json::value_t::object: + { + JSON_THROW(invalid_iterator::create(213, "cannot compare order of object iterators")); + } + + case basic_json::value_t::array: { - // from c (1 byte) to \x (2 bytes) - return res + 1; + return (m_it.array_iterator < other.m_it.array_iterator); } default: { - if (c >= 0x00 and c <= 0x1f) - { - // from c (1 byte) to \uxxxx (6 bytes) - return res + 5; - } - else - { - return res; - } + return (m_it.primitive_iterator < other.m_it.primitive_iterator); } } - }); - } - - /*! - @brief escape a string - - Escape a string by replacing certain special characters by a sequence of - an escape character (backslash) and another character and other control - characters by a sequence of "\u" followed by a four-digit hex - representation. + } - @param[in] s the string to escape - @return the escaped string + /*! + @brief comparison: less than or equal + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator<=(const iter_impl& other) const + { + return not other.operator < (*this); + } - @complexity Linear in the length of string @a s. - */ - static string_t escape_string(const string_t& s) - { - const auto space = extra_space(s); - if (space == 0) + /*! + @brief comparison: greater than + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator>(const iter_impl& other) const { - return s; + return not operator<=(other); } - // create a result string of necessary size - string_t result(s.size() + space, '\\'); - std::size_t pos = 0; + /*! + @brief comparison: greater than or equal + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator>=(const iter_impl& other) const + { + return not operator<(other); + } - for (const auto& c : s) + /*! + @brief add to iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl& operator+=(difference_type i) { - switch (c) + assert(m_object != nullptr); + + switch (m_object->m_type) { - // quotation mark (0x22) - case '"': + case basic_json::value_t::object: { - result[pos + 1] = '"'; - pos += 2; - break; + JSON_THROW(invalid_iterator::create(209, "cannot use offsets with object iterators")); } - // reverse solidus (0x5c) - case '\\': + case basic_json::value_t::array: { - // nothing to change - pos += 2; + std::advance(m_it.array_iterator, i); break; } - // backspace (0x08) - case '\b': + default: { - result[pos + 1] = 'b'; - pos += 2; + m_it.primitive_iterator += i; break; } + } - // formfeed (0x0c) - case '\f': - { - result[pos + 1] = 'f'; - pos += 2; - break; - } + return *this; + } - // newline (0x0a) - case '\n': - { - result[pos + 1] = 'n'; - pos += 2; - break; - } + /*! + @brief subtract from iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl& operator-=(difference_type i) + { + return operator+=(-i); + } + + /*! + @brief add to iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl operator+(difference_type i) + { + auto result = *this; + result += i; + return result; + } + + /*! + @brief subtract from iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl operator-(difference_type i) + { + auto result = *this; + result -= i; + return result; + } - // carriage return (0x0d) - case '\r': + /*! + @brief return difference + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + difference_type operator-(const iter_impl& other) const + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case basic_json::value_t::object: { - result[pos + 1] = 'r'; - pos += 2; - break; + JSON_THROW(invalid_iterator::create(209, "cannot use offsets with object iterators")); } - // horizontal tab (0x09) - case '\t': + case basic_json::value_t::array: { - result[pos + 1] = 't'; - pos += 2; - break; + return m_it.array_iterator - other.m_it.array_iterator; } default: { - if (c >= 0x00 and c <= 0x1f) - { - // convert a number 0..15 to its hex representation - // (0..f) - static const char hexify[16] = - { - '0', '1', '2', '3', '4', '5', '6', '7', - '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' - }; - - // print character c as \uxxxx - for (const char m : - { 'u', '0', '0', hexify[c >> 4], hexify[c & 0x0f] - }) - { - result[++pos] = m; - } - - ++pos; - } - else - { - // all other characters are added as-is - result[pos++] = c; - } - break; + return m_it.primitive_iterator - other.m_it.primitive_iterator; } } } - return result; - } - - /*! - @brief internal implementation of the serialization function - - This function is called by the public member function dump and organizes - the serialization internally. The indentation level is propagated as - additional parameter. In case of arrays and objects, the function is - called recursively. Note that - - - strings and object keys are escaped using `escape_string()` - - integer numbers are converted implicitly via `operator<<` - - floating-point numbers are converted to a string using `"%g"` format - - @param[out] o stream to write to - @param[in] pretty_print whether the output shall be pretty-printed - @param[in] indent_step the indent level - @param[in] current_indent the current indent level (only used internally) - */ - void dump(std::ostream& o, - const bool pretty_print, - const unsigned int indent_step, - const unsigned int current_indent = 0) const - { - // variable to hold indentation for recursive calls - unsigned int new_indent = current_indent; - - switch (m_type) + /*! + @brief access to successor + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + reference operator[](difference_type n) const { - case value_t::object: + assert(m_object != nullptr); + + switch (m_object->m_type) { - if (m_value.object->empty()) + case basic_json::value_t::object: { - o << "{}"; - return; + JSON_THROW(invalid_iterator::create(208, "cannot use operator[] for object iterators")); } - o << "{"; + case basic_json::value_t::array: + { + return *std::next(m_it.array_iterator, n); + } - // increase indentation - if (pretty_print) + case basic_json::value_t::null: { - new_indent += indent_step; - o << "\n"; + JSON_THROW(invalid_iterator::create(214, "cannot get value")); } - for (auto i = m_value.object->cbegin(); i != m_value.object->cend(); ++i) + default: { - if (i != m_value.object->cbegin()) + if (m_it.primitive_iterator.get_value() == -n) { - o << (pretty_print ? ",\n" : ","); + return *m_object; } - o << string_t(new_indent, ' ') << "\"" - << escape_string(i->first) << "\":" - << (pretty_print ? " " : ""); - i->second.dump(o, pretty_print, indent_step, new_indent); - } - // decrease indentation - if (pretty_print) - { - new_indent -= indent_step; - o << "\n"; + JSON_THROW(invalid_iterator::create(214, "cannot get value")); } - - o << string_t(new_indent, ' ') + "}"; - return; } + } - case value_t::array: + /*! + @brief return the key of an object iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + typename object_t::key_type key() const + { + assert(m_object != nullptr); + + if (m_object->is_object()) { - if (m_value.array->empty()) - { - o << "[]"; - return; - } + return m_it.object_iterator->first; + } - o << "["; + JSON_THROW(invalid_iterator::create(207, "cannot use key() for non-object iterators")); + } - // increase indentation - if (pretty_print) - { - new_indent += indent_step; - o << "\n"; - } + /*! + @brief return the value of an iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + reference value() const + { + return operator*(); + } - for (auto i = m_value.array->cbegin(); i != m_value.array->cend(); ++i) - { - if (i != m_value.array->cbegin()) - { - o << (pretty_print ? ",\n" : ","); - } - o << string_t(new_indent, ' '); - i->dump(o, pretty_print, indent_step, new_indent); - } + private: + /// associated JSON instance + pointer m_object = nullptr; + /// the actual iterator of the associated instance + internal_iterator m_it = internal_iterator(); + }; + + /*! + @brief a template for a reverse iterator class + + @tparam Base the base iterator type to reverse. Valid types are @ref + iterator (to create @ref reverse_iterator) and @ref const_iterator (to + create @ref const_reverse_iterator). + + @requirement The class satisfies the following concept requirements: + - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator): + The iterator that can be moved to point (forward and backward) to any + element in constant time. + - [OutputIterator](http://en.cppreference.com/w/cpp/concept/OutputIterator): + It is possible to write to the pointed-to element (only if @a Base is + @ref iterator). + + @since version 1.0.0 + */ + template + class json_reverse_iterator : public std::reverse_iterator + { + public: + /// shortcut to the reverse iterator adaptor + using base_iterator = std::reverse_iterator; + /// the reference type for the pointed-to element + using reference = typename Base::reference; - // decrease indentation - if (pretty_print) - { - new_indent -= indent_step; - o << "\n"; - } + /// create reverse iterator from iterator + json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept + : base_iterator(it) + {} - o << string_t(new_indent, ' ') << "]"; - return; - } + /// create reverse iterator from base class + json_reverse_iterator(const base_iterator& it) noexcept + : base_iterator(it) + {} - case value_t::string: - { - o << string_t("\"") << escape_string(*m_value.string) << "\""; - return; - } + /// post-increment (it++) + json_reverse_iterator operator++(int) + { + return base_iterator::operator++(1); + } - case value_t::boolean: - { - o << (m_value.boolean ? "true" : "false"); - return; - } + /// pre-increment (++it) + json_reverse_iterator& operator++() + { + base_iterator::operator++(); + return *this; + } - case value_t::number_integer: - { - o << m_value.number_integer; - return; - } + /// post-decrement (it--) + json_reverse_iterator operator--(int) + { + return base_iterator::operator--(1); + } - case value_t::number_unsigned: - { - o << m_value.number_unsigned; - return; - } + /// pre-decrement (--it) + json_reverse_iterator& operator--() + { + base_iterator::operator--(); + return *this; + } - case value_t::number_float: - { - if (m_value.number_float == 0) - { - // special case for zero to get "0.0"/"-0.0" - o << (std::signbit(m_value.number_float) ? "-0.0" : "0.0"); - } - else - { - o << m_value.number_float; - } - return; - } + /// add to iterator + json_reverse_iterator& operator+=(difference_type i) + { + base_iterator::operator+=(i); + return *this; + } - case value_t::discarded: - { - o << ""; - return; - } + /// add to iterator + json_reverse_iterator operator+(difference_type i) const + { + auto result = *this; + result += i; + return result; + } - case value_t::null: - { - o << "null"; - return; - } + /// subtract from iterator + json_reverse_iterator operator-(difference_type i) const + { + auto result = *this; + result -= i; + return result; } - } - private: - ////////////////////// - // member variables // - ////////////////////// + /// return difference + difference_type operator-(const json_reverse_iterator& other) const + { + return this->base() - other.base(); + } - /// the type of the current element - value_t m_type = value_t::null; + /// access to successor + reference operator[](difference_type n) const + { + return *(this->operator+(n)); + } - /// the value of the current element - json_value m_value = {}; + /// return the key of an object iterator + typename object_t::key_type key() const + { + auto it = --this->base(); + return it.key(); + } + + /// return the value of an iterator + reference value() const + { + auto it = --this->base(); + return it.operator * (); + } + }; private: - /////////////// - // iterators // - /////////////// - - /*! - @brief an iterator for primitive JSON types + //////////////////// + // input adapters // + //////////////////// - This class models an iterator for primitive JSON types (boolean, number, - string). It's only purpose is to allow the iterator/const_iterator classes - to "iterate" over primitive values. Internally, the iterator is modeled by - a `difference_type` variable. Value begin_value (`0`) models the begin, - end_value (`1`) models past the end. - */ - class primitive_iterator_t + /// abstract input adapter interface + class input_adapter { public: - /// set iterator to a defined beginning - void set_begin() noexcept + virtual int get_character() = 0; + virtual std::string read(size_t offset, size_t length) = 0; + virtual ~input_adapter() {} + + // native support + + /// input adapter for input stream + static std::shared_ptr create(std::istream& i, const size_t buffer_size = 16384) { - m_it = begin_value; + return std::shared_ptr(new cached_input_stream_adapter(i, buffer_size)); } - /// set iterator to a defined past the end - void set_end() noexcept + /// input adapter for input stream + static std::shared_ptr create(std::istream&& i, const size_t buffer_size = 16384) { - m_it = end_value; + return std::shared_ptr(new cached_input_stream_adapter(i, buffer_size)); } - /// return whether the iterator can be dereferenced - constexpr bool is_begin() const noexcept + /// input adapter for buffer + static std::shared_ptr create(const char* b, size_t l) { - return (m_it == begin_value); + return std::shared_ptr(new input_buffer_adapter(b, l)); } - /// return whether the iterator is at end - constexpr bool is_end() const noexcept + // derived support + + /// input adapter for string literal + template::value and + std::is_integral::type>::value and + sizeof(typename std::remove_pointer::type) == 1, int>::type = 0> + static std::shared_ptr create(CharT b) { - return (m_it == end_value); + return create(reinterpret_cast(b), + std::strlen(reinterpret_cast(b))); } - /// return reference to the value to change and compare - operator difference_type& () noexcept + /// input adapter for iterator range with contiguous storage + template::iterator_category, std::random_access_iterator_tag>::value + , int>::type + = 0> + static std::shared_ptr create(IteratorType first, IteratorType last) { - return m_it; + // assertion to check that the iterator range is indeed contiguous, + // see http://stackoverflow.com/a/35008842/266378 for more discussion + assert(std::accumulate(first, last, std::pair(true, 0), + [&first](std::pair res, decltype(*first) val) + { + res.first &= (val == *(std::next(std::addressof(*first), res.second++))); + return res; + }).first); + + // assertion to check that each element is 1 byte long + static_assert(sizeof(typename std::iterator_traits::value_type) == 1, + "each element in the iterator range must have the size of 1 byte"); + + return create(reinterpret_cast(&(*first)), + static_cast(std::distance(first, last))); } - /// return value to compare - constexpr operator difference_type () const noexcept + /// input adapter for array + template + static std::shared_ptr create(T (&array)[N]) { - return m_it; + // delegate the call to the iterator-range overload + return create(std::begin(array), std::end(array)); } - private: - static constexpr difference_type begin_value = 0; - static constexpr difference_type end_value = begin_value + 1; - - /// iterator as signed integer type - difference_type m_it = std::numeric_limits::denorm_min(); + /// input adapter for contiguous container + template::value and + std::is_base_of< + std::random_access_iterator_tag, + typename std::iterator_traits()))>::iterator_category>::value + , int>::type = 0> + static std::shared_ptr create(const ContiguousContainer& c) + { + // delegate the call to the iterator-range overload + return create(std::begin(c), std::end(c)); + } }; - /*! - @brief an iterator value - - @note This structure could easily be a union, but MSVC currently does not - allow unions members with complex constructors, see - https://github.com/nlohmann/json/pull/105. - */ - struct internal_iterator - { - /// iterator for JSON objects - typename object_t::iterator object_iterator; - /// iterator for JSON arrays - typename array_t::iterator array_iterator; - /// generic iterator for all other types - primitive_iterator_t primitive_iterator; - - /// create an uninitialized internal_iterator - internal_iterator() noexcept - : object_iterator(), array_iterator(), primitive_iterator() - {} - }; + /// a type to simplify interfaces + using input_adapter_t = std::shared_ptr; - /// proxy class for the iterator_wrapper functions - template - class iteration_proxy + /// input adapter for cached stream input + class cached_input_stream_adapter : public input_adapter { - private: - /// helper class for iteration - class iteration_proxy_internal + public: + cached_input_stream_adapter(std::istream& i, const size_t buffer_size) + : is(i), start_position(is.tellg()), buffer(buffer_size, '\0') { - private: - /// the iterator - IteratorType anchor; - /// an index for arrays (used to create key names) - size_t array_index = 0; + // immediately abort if stream is erroneous + if (JSON_UNLIKELY(i.fail())) + { + JSON_THROW(parse_error::create(111, 0, "bad input stream")); + } - public: - explicit iteration_proxy_internal(IteratorType it) noexcept - : anchor(it) - {} + // initial fill + is.read(buffer.data(), static_cast(buffer.size())); + // store number of bytes in the buffer + fill_size = static_cast(is.gcount()); - /// dereference operator (needed for range-based for) - iteration_proxy_internal& operator*() + // skip byte order mark + if (fill_size >= 3 and buffer[0] == '\xEF' and buffer[1] == '\xBB' and buffer[2] == '\xBF') { - return *this; + buffer_pos += 3; + processed_chars += 3; } + } - /// increment operator (needed for range-based for) - iteration_proxy_internal& operator++() + ~cached_input_stream_adapter() override + { + // clear stream flags + is.clear(); + // We initially read a lot of characters into the buffer, and we + // may not have processed all of them. Therefore, we need to + // "rewind" the stream after the last processed char. + is.seekg(start_position + static_cast(processed_chars)); + // clear stream flags + is.clear(); + } + + int get_character() override + { + // check if refilling is necessary and possible + if (buffer_pos == fill_size and not eof) { - ++anchor; - ++array_index; + // refill + is.read(buffer.data(), static_cast(buffer.size())); + // store number of bytes in the buffer + fill_size = static_cast(is.gcount()); - return *this; - } + // the buffer is ready + buffer_pos = 0; - /// inequality operator (needed for range-based for) - bool operator!= (const iteration_proxy_internal& o) const - { - return anchor != o.anchor; + // remember that filling did not yield new input + if (fill_size == 0) + { + eof = true; + return std::char_traits::eof(); + } } - /// return key of the iterator - typename basic_json::string_t key() const - { - assert(anchor.m_object != nullptr); + ++processed_chars; + return buffer[buffer_pos++] & 0xFF;; + } - switch (anchor.m_object->type()) - { - // use integer array index as key - case value_t::array: - { - return std::to_string(array_index); - } + std::string read(size_t offset, size_t length) override + { + // create buffer + std::string result(length, '\0'); - // use key from the object - case value_t::object: - { - return anchor.key(); - } + // save stream position + auto current_pos = is.tellg(); + // save stream flags + auto flags = is.rdstate(); - // use an empty key for all primitive types - default: - { - return ""; - } - } - } + // clear stream flags + is.clear(); + // set stream position + is.seekg(static_cast(offset)); + // read bytes + is.read(&result[0], static_cast(length)); + + // reset stream position + is.seekg(current_pos); + // reset stream flags + is.setstate(flags); + + return result; + } + + private: + /// the associated input stream + std::istream& is; - /// return value of the iterator - typename IteratorType::reference value() const - { - return anchor.value(); - } - }; + /// chars returned via get_character() + size_t processed_chars = 0; + /// chars processed in the current buffer + size_t buffer_pos = 0; - /// the container to iterate - typename IteratorType::reference container; + /// whether stream reached eof + bool eof = false; + /// how many chars have been copied to the buffer by last (re)fill + size_t fill_size = 0; - public: - /// construct iteration proxy from a container - explicit iteration_proxy(typename IteratorType::reference cont) - : container(cont) - {} + /// position of the stream when we started + const std::streampos start_position; - /// return iterator begin (needed for range-based for) - iteration_proxy_internal begin() noexcept + /// internal buffer + std::vector buffer; + }; + + /// input adapter for buffer input + class input_buffer_adapter : public input_adapter + { + public: + input_buffer_adapter(const char* b, size_t l) + : input_adapter(), cursor(b), limit(b + l), start(b) { - return iteration_proxy_internal(container.begin()); + // skip byte order mark + if (l >= 3 and b[0] == '\xEF' and b[1] == '\xBB' and b[2] == '\xBF') + { + cursor += 3; + } } - /// return iterator end (needed for range-based for) - iteration_proxy_internal end() noexcept + // delete because of pointer members + input_buffer_adapter(const input_buffer_adapter&) = delete; + input_buffer_adapter& operator=(input_buffer_adapter&) = delete; + + int get_character() override { - return iteration_proxy_internal(container.end()); + if (JSON_LIKELY(cursor < limit)) + { + return *(cursor++) & 0xFF; + } + else + { + return std::char_traits::eof(); + } } - }; - public: - /*! - @brief a const random access iterator for the @ref basic_json class + std::string read(size_t offset, size_t length) override + { + // avoid reading too many characters + const size_t max_length = static_cast(limit - start); + return std::string(start + offset, std::min(length, max_length - offset)); + } - This class implements a const iterator for the @ref basic_json class. From - this class, the @ref iterator class is derived. + private: + /// pointer to the current character + const char* cursor; + /// pointer past the last character + const char* limit; + /// pointer to the first character + const char* start; + }; - @note An iterator is called *initialized* when a pointer to a JSON value - has been set (e.g., by a constructor or a copy assignment). If the - iterator is default-constructed, it is *uninitialized* and most - methods are undefined. **The library uses assertions to detect calls - on uninitialized iterators.** + ////////////////////////////////////////// + // binary serialization/deserialization // + ////////////////////////////////////////// - @requirement The class satisfies the following concept requirements: - - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator): - The iterator that can be moved to point (forward and backward) to any - element in constant time. + /// @name binary serialization/deserialization support + /// @{ - @since version 1.0.0 + private: + /*! + @brief deserialization of CBOR and MessagePack values */ - class const_iterator : public std::iterator + class binary_reader { - /// allow basic_json to access private members - friend class basic_json; - public: - /// the type of the values when the iterator is dereferenced - using value_type = typename basic_json::value_type; - /// a type to represent differences between iterators - using difference_type = typename basic_json::difference_type; - /// defines a pointer to the type iterated over (value_type) - using pointer = typename basic_json::const_pointer; - /// defines a reference to the type iterated over (value_type) - using reference = typename basic_json::const_reference; - /// the category of the iterator - using iterator_category = std::bidirectional_iterator_tag; + /*! + @brief create a binary reader - /// default constructor - const_iterator() = default; + @param[in] adapter input adapter to read from + */ + explicit binary_reader(input_adapter_t adapter) + : ia(adapter), is_little_endian(little_endianess()) + { + assert(ia); + } /*! - @brief constructor for a given JSON instance - @param[in] object pointer to a JSON object for this iterator - @pre object != nullptr - @post The iterator is initialized; i.e. `m_object != nullptr`. + @brief create a JSON value from CBOR input + + @param[in] get_char whether a new character should be retrieved from + the input (true, default) or whether the last + read character should be considered instead + + @return JSON value created from CBOR input + + @throw parse_error.110 if input ended unexpectedly + @throw parse_error.112 if unsupported byte was read */ - explicit const_iterator(pointer object) noexcept - : m_object(object) + basic_json parse_cbor(const bool get_char = true) { - assert(m_object != nullptr); - - switch (m_object->m_type) + switch (get_char ? get() : current) { - case basic_json::value_t::object: + // EOF + case std::char_traits::eof(): { - m_it.object_iterator = typename object_t::iterator(); - break; + JSON_THROW(parse_error::create(110, chars_read, "unexpected end of input")); } - case basic_json::value_t::array: + // Integer 0x00..0x17 (0..23) + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x08: + case 0x09: + case 0x0a: + case 0x0b: + case 0x0c: + case 0x0d: + case 0x0e: + case 0x0f: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: { - m_it.array_iterator = typename array_t::iterator(); - break; + return static_cast(current); } - default: + case 0x18: // Unsigned integer (one-byte uint8_t follows) { - m_it.primitive_iterator = primitive_iterator_t(); - break; + return get_number(); } - } - } - /*! - @brief copy constructor given a non-const iterator - @param[in] other iterator to copy from - @note It is not checked whether @a other is initialized. - */ - explicit const_iterator(const iterator& other) noexcept - : m_object(other.m_object) - { - if (m_object != nullptr) - { - switch (m_object->m_type) + case 0x19: // Unsigned integer (two-byte uint16_t follows) + { + return get_number(); + } + + case 0x1a: // Unsigned integer (four-byte uint32_t follows) + { + return get_number(); + } + + case 0x1b: // Unsigned integer (eight-byte uint64_t follows) + { + return get_number(); + } + + // Negative integer -1-0x00..-1-0x17 (-1..-24) + case 0x20: + case 0x21: + case 0x22: + case 0x23: + case 0x24: + case 0x25: + case 0x26: + case 0x27: + case 0x28: + case 0x29: + case 0x2a: + case 0x2b: + case 0x2c: + case 0x2d: + case 0x2e: + case 0x2f: + case 0x30: + case 0x31: + case 0x32: + case 0x33: + case 0x34: + case 0x35: + case 0x36: + case 0x37: + { + return static_cast(0x20 - 1 - current); + } + + case 0x38: // Negative integer (one-byte uint8_t follows) + { + // must be uint8_t ! + return static_cast(-1) - get_number(); + } + + case 0x39: // Negative integer -1-n (two-byte uint16_t follows) + { + return static_cast(-1) - get_number(); + } + + case 0x3a: // Negative integer -1-n (four-byte uint32_t follows) + { + return static_cast(-1) - get_number(); + } + + case 0x3b: // Negative integer -1-n (eight-byte uint64_t follows) + { + return static_cast(-1) - static_cast(get_number()); + } + + // UTF-8 string (0x00..0x17 bytes follow) + case 0x60: + case 0x61: + case 0x62: + case 0x63: + case 0x64: + case 0x65: + case 0x66: + case 0x67: + case 0x68: + case 0x69: + case 0x6a: + case 0x6b: + case 0x6c: + case 0x6d: + case 0x6e: + case 0x6f: + case 0x70: + case 0x71: + case 0x72: + case 0x73: + case 0x74: + case 0x75: + case 0x76: + case 0x77: + case 0x78: // UTF-8 string (one-byte uint8_t for n follows) + case 0x79: // UTF-8 string (two-byte uint16_t for n follow) + case 0x7a: // UTF-8 string (four-byte uint32_t for n follow) + case 0x7b: // UTF-8 string (eight-byte uint64_t for n follow) + case 0x7f: // UTF-8 string (indefinite length) + { + return get_cbor_string(); + } + + // array (0x00..0x17 data items follow) + case 0x80: + case 0x81: + case 0x82: + case 0x83: + case 0x84: + case 0x85: + case 0x86: + case 0x87: + case 0x88: + case 0x89: + case 0x8a: + case 0x8b: + case 0x8c: + case 0x8d: + case 0x8e: + case 0x8f: + case 0x90: + case 0x91: + case 0x92: + case 0x93: + case 0x94: + case 0x95: + case 0x96: + case 0x97: + { + basic_json result = value_t::array; + const auto len = static_cast(current & 0x1f); + for (size_t i = 0; i < len; ++i) + { + result.push_back(parse_cbor()); + } + return result; + } + + case 0x98: // array (one-byte uint8_t for n follows) { - case basic_json::value_t::object: + basic_json result = value_t::array; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) { - m_it.object_iterator = other.m_it.object_iterator; - break; + result.push_back(parse_cbor()); } + return result; + } - case basic_json::value_t::array: + case 0x99: // array (two-byte uint16_t for n follow) + { + basic_json result = value_t::array; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) { - m_it.array_iterator = other.m_it.array_iterator; - break; + result.push_back(parse_cbor()); } + return result; + } - default: + case 0x9a: // array (four-byte uint32_t for n follow) + { + basic_json result = value_t::array; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) { - m_it.primitive_iterator = other.m_it.primitive_iterator; - break; + result.push_back(parse_cbor()); } + return result; } - } - } - /*! - @brief copy constructor - @param[in] other iterator to copy from - @note It is not checked whether @a other is initialized. - */ - const_iterator(const const_iterator& other) noexcept - : m_object(other.m_object), m_it(other.m_it) - {} + case 0x9b: // array (eight-byte uint64_t for n follow) + { + basic_json result = value_t::array; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) + { + result.push_back(parse_cbor()); + } + return result; + } - /*! - @brief copy assignment - @param[in,out] other iterator to copy from - @note It is not checked whether @a other is initialized. - */ - const_iterator& operator=(const_iterator other) noexcept( - std::is_nothrow_move_constructible::value and - std::is_nothrow_move_assignable::value and - std::is_nothrow_move_constructible::value and - std::is_nothrow_move_assignable::value - ) - { - std::swap(m_object, other.m_object); - std::swap(m_it, other.m_it); - return *this; - } + case 0x9f: // array (indefinite length) + { + basic_json result = value_t::array; + while (get() != 0xff) + { + result.push_back(parse_cbor(false)); + } + return result; + } - private: - /*! - @brief set the iterator to the first value - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - void set_begin() noexcept - { - assert(m_object != nullptr); + // map (0x00..0x17 pairs of data items follow) + case 0xa0: + case 0xa1: + case 0xa2: + case 0xa3: + case 0xa4: + case 0xa5: + case 0xa6: + case 0xa7: + case 0xa8: + case 0xa9: + case 0xaa: + case 0xab: + case 0xac: + case 0xad: + case 0xae: + case 0xaf: + case 0xb0: + case 0xb1: + case 0xb2: + case 0xb3: + case 0xb4: + case 0xb5: + case 0xb6: + case 0xb7: + { + basic_json result = value_t::object; + const auto len = static_cast(current & 0x1f); + for (size_t i = 0; i < len; ++i) + { + get(); + auto key = get_cbor_string(); + result[key] = parse_cbor(); + } + return result; + } - switch (m_object->m_type) - { - case basic_json::value_t::object: + case 0xb8: // map (one-byte uint8_t for n follows) { - m_it.object_iterator = m_object->m_value.object->begin(); - break; + basic_json result = value_t::object; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) + { + get(); + auto key = get_cbor_string(); + result[key] = parse_cbor(); + } + return result; } - case basic_json::value_t::array: + case 0xb9: // map (two-byte uint16_t for n follow) { - m_it.array_iterator = m_object->m_value.array->begin(); - break; + basic_json result = value_t::object; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) + { + get(); + auto key = get_cbor_string(); + result[key] = parse_cbor(); + } + return result; } - case basic_json::value_t::null: + case 0xba: // map (four-byte uint32_t for n follow) { - // set to end so begin()==end() is true: null is empty - m_it.primitive_iterator.set_end(); - break; + basic_json result = value_t::object; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) + { + get(); + auto key = get_cbor_string(); + result[key] = parse_cbor(); + } + return result; } - default: + case 0xbb: // map (eight-byte uint64_t for n follow) { - m_it.primitive_iterator.set_begin(); - break; + basic_json result = value_t::object; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) + { + get(); + auto key = get_cbor_string(); + result[key] = parse_cbor(); + } + return result; + } + + case 0xbf: // map (indefinite length) + { + basic_json result = value_t::object; + while (get() != 0xff) + { + auto key = get_cbor_string(); + result[key] = parse_cbor(); + } + return result; + } + + case 0xf4: // false + { + return false; + } + + case 0xf5: // true + { + return true; + } + + case 0xf6: // null + { + return value_t::null; + } + + case 0xf9: // Half-Precision Float (two-byte IEEE 754) + { + const int byte1 = get(); + check_eof(); + const int byte2 = get(); + check_eof(); + + // code from RFC 7049, Appendix D, Figure 3: + // As half-precision floating-point numbers were only added + // to IEEE 754 in 2008, today's programming platforms often + // still only have limited support for them. It is very + // easy to include at least decoding support for them even + // without such support. An example of a small decoder for + // half-precision floating-point numbers in the C language + // is shown in Fig. 3. + const int half = (byte1 << 8) + byte2; + const int exp = (half >> 10) & 0x1f; + const int mant = half & 0x3ff; + double val; + if (exp == 0) + { + val = std::ldexp(mant, -24); + } + else if (exp != 31) + { + val = std::ldexp(mant + 1024, exp - 25); + } + else + { + val = mant == 0 + ? std::numeric_limits::infinity() + : std::numeric_limits::quiet_NaN(); + } + return (half & 0x8000) != 0 ? -val : val; + } + + case 0xfa: // Single-Precision Float (four-byte IEEE 754) + { + return get_number(); + } + + case 0xfb: // Double-Precision Float (eight-byte IEEE 754) + { + return get_number(); + } + + default: // anything else (0xFF is handled inside the other types) + { + std::stringstream ss; + ss << std::setw(2) << std::setfill('0') << std::hex << current; + JSON_THROW(parse_error::create(112, chars_read, "error reading CBOR; last byte: 0x" + ss.str())); } } } /*! - @brief set the iterator past the last value - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief create a JSON value from MessagePack input + + @return JSON value created from MessagePack input + + @throw parse_error.110 if input ended unexpectedly + @throw parse_error.112 if unsupported byte was read */ - void set_end() noexcept - { - assert(m_object != nullptr); + basic_json parse_msgpack() + { + switch (get()) + { + // EOF + case std::char_traits::eof(): + { + JSON_THROW(parse_error::create(110, chars_read, "unexpected end of input")); + } + + // positive fixint + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x08: + case 0x09: + case 0x0a: + case 0x0b: + case 0x0c: + case 0x0d: + case 0x0e: + case 0x0f: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + case 0x18: + case 0x19: + case 0x1a: + case 0x1b: + case 0x1c: + case 0x1d: + case 0x1e: + case 0x1f: + case 0x20: + case 0x21: + case 0x22: + case 0x23: + case 0x24: + case 0x25: + case 0x26: + case 0x27: + case 0x28: + case 0x29: + case 0x2a: + case 0x2b: + case 0x2c: + case 0x2d: + case 0x2e: + case 0x2f: + case 0x30: + case 0x31: + case 0x32: + case 0x33: + case 0x34: + case 0x35: + case 0x36: + case 0x37: + case 0x38: + case 0x39: + case 0x3a: + case 0x3b: + case 0x3c: + case 0x3d: + case 0x3e: + case 0x3f: + case 0x40: + case 0x41: + case 0x42: + case 0x43: + case 0x44: + case 0x45: + case 0x46: + case 0x47: + case 0x48: + case 0x49: + case 0x4a: + case 0x4b: + case 0x4c: + case 0x4d: + case 0x4e: + case 0x4f: + case 0x50: + case 0x51: + case 0x52: + case 0x53: + case 0x54: + case 0x55: + case 0x56: + case 0x57: + case 0x58: + case 0x59: + case 0x5a: + case 0x5b: + case 0x5c: + case 0x5d: + case 0x5e: + case 0x5f: + case 0x60: + case 0x61: + case 0x62: + case 0x63: + case 0x64: + case 0x65: + case 0x66: + case 0x67: + case 0x68: + case 0x69: + case 0x6a: + case 0x6b: + case 0x6c: + case 0x6d: + case 0x6e: + case 0x6f: + case 0x70: + case 0x71: + case 0x72: + case 0x73: + case 0x74: + case 0x75: + case 0x76: + case 0x77: + case 0x78: + case 0x79: + case 0x7a: + case 0x7b: + case 0x7c: + case 0x7d: + case 0x7e: + case 0x7f: + { + return static_cast(current); + } + + // fixmap + case 0x80: + case 0x81: + case 0x82: + case 0x83: + case 0x84: + case 0x85: + case 0x86: + case 0x87: + case 0x88: + case 0x89: + case 0x8a: + case 0x8b: + case 0x8c: + case 0x8d: + case 0x8e: + case 0x8f: + { + basic_json result = value_t::object; + const auto len = static_cast(current & 0x0f); + for (size_t i = 0; i < len; ++i) + { + get(); + auto key = get_msgpack_string(); + result[key] = parse_msgpack(); + } + return result; + } - switch (m_object->m_type) - { - case basic_json::value_t::object: + // fixarray + case 0x90: + case 0x91: + case 0x92: + case 0x93: + case 0x94: + case 0x95: + case 0x96: + case 0x97: + case 0x98: + case 0x99: + case 0x9a: + case 0x9b: + case 0x9c: + case 0x9d: + case 0x9e: + case 0x9f: + { + basic_json result = value_t::array; + const auto len = static_cast(current & 0x0f); + for (size_t i = 0; i < len; ++i) + { + result.push_back(parse_msgpack()); + } + return result; + } + + // fixstr + case 0xa0: + case 0xa1: + case 0xa2: + case 0xa3: + case 0xa4: + case 0xa5: + case 0xa6: + case 0xa7: + case 0xa8: + case 0xa9: + case 0xaa: + case 0xab: + case 0xac: + case 0xad: + case 0xae: + case 0xaf: + case 0xb0: + case 0xb1: + case 0xb2: + case 0xb3: + case 0xb4: + case 0xb5: + case 0xb6: + case 0xb7: + case 0xb8: + case 0xb9: + case 0xba: + case 0xbb: + case 0xbc: + case 0xbd: + case 0xbe: + case 0xbf: + { + return get_msgpack_string(); + } + + case 0xc0: // nil + { + return value_t::null; + } + + case 0xc2: // false + { + return false; + } + + case 0xc3: // true + { + return true; + } + + case 0xca: // float 32 + { + return get_number(); + } + + case 0xcb: // float 64 + { + return get_number(); + } + + case 0xcc: // uint 8 { - m_it.object_iterator = m_object->m_value.object->end(); - break; + return get_number(); } - case basic_json::value_t::array: + case 0xcd: // uint 16 { - m_it.array_iterator = m_object->m_value.array->end(); - break; + return get_number(); } - default: + case 0xce: // uint 32 { - m_it.primitive_iterator.set_end(); - break; + return get_number(); } - } - } - public: - /*! - @brief return a reference to the value pointed to by the iterator - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - reference operator*() const - { - assert(m_object != nullptr); + case 0xcf: // uint 64 + { + return get_number(); + } - switch (m_object->m_type) - { - case basic_json::value_t::object: + case 0xd0: // int 8 { - assert(m_it.object_iterator != m_object->m_value.object->end()); - return m_it.object_iterator->second; + return get_number(); } - case basic_json::value_t::array: + case 0xd1: // int 16 { - assert(m_it.array_iterator != m_object->m_value.array->end()); - return *m_it.array_iterator; + return get_number(); } - case basic_json::value_t::null: + case 0xd2: // int 32 { - throw std::out_of_range("cannot get value"); + return get_number(); } - default: + case 0xd3: // int 64 { - if (m_it.primitive_iterator.is_begin()) - { - return *m_object; - } - else - { - throw std::out_of_range("cannot get value"); - } + return get_number(); } - } - } - /*! - @brief dereference the iterator - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - pointer operator->() const - { - assert(m_object != nullptr); + case 0xd9: // str 8 + case 0xda: // str 16 + case 0xdb: // str 32 + { + return get_msgpack_string(); + } - switch (m_object->m_type) - { - case basic_json::value_t::object: + case 0xdc: // array 16 { - assert(m_it.object_iterator != m_object->m_value.object->end()); - return &(m_it.object_iterator->second); + basic_json result = value_t::array; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) + { + result.push_back(parse_msgpack()); + } + return result; } - case basic_json::value_t::array: + case 0xdd: // array 32 { - assert(m_it.array_iterator != m_object->m_value.array->end()); - return &*m_it.array_iterator; + basic_json result = value_t::array; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) + { + result.push_back(parse_msgpack()); + } + return result; } - default: + case 0xde: // map 16 { - if (m_it.primitive_iterator.is_begin()) + basic_json result = value_t::object; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) { - return m_object; + get(); + auto key = get_msgpack_string(); + result[key] = parse_msgpack(); } - else + return result; + } + + case 0xdf: // map 32 + { + basic_json result = value_t::object; + const auto len = static_cast(get_number()); + for (size_t i = 0; i < len; ++i) { - throw std::out_of_range("cannot get value"); + get(); + auto key = get_msgpack_string(); + result[key] = parse_msgpack(); } + return result; + } + + // positive fixint + case 0xe0: + case 0xe1: + case 0xe2: + case 0xe3: + case 0xe4: + case 0xe5: + case 0xe6: + case 0xe7: + case 0xe8: + case 0xe9: + case 0xea: + case 0xeb: + case 0xec: + case 0xed: + case 0xee: + case 0xef: + case 0xf0: + case 0xf1: + case 0xf2: + case 0xf3: + case 0xf4: + case 0xf5: + case 0xf6: + case 0xf7: + case 0xf8: + case 0xf9: + case 0xfa: + case 0xfb: + case 0xfc: + case 0xfd: + case 0xfe: + case 0xff: + { + return static_cast(current); + } + + default: // anything else + { + std::stringstream ss; + ss << std::setw(2) << std::setfill('0') << std::hex << current; + JSON_THROW(parse_error::create(112, chars_read, "error reading MessagePack; last byte: 0x" + ss.str())); } } } /*! - @brief post-increment (it++) - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief determine system byte order + + @return true iff system's byte order is little endian + + @note from http://stackoverflow.com/a/1001328/266378 */ - const_iterator operator++(int) + static bool little_endianess() noexcept { - auto result = *this; - ++(*this); - return result; + int num = 1; + return (*reinterpret_cast(&num) == 1); } + private: /*! - @brief pre-increment (++it) - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief get next character from the input + + This function provides the interface to the used input adapter. It does + not throw in case the input reached EOF, but returns + `std::char_traits::eof()` in that case. + + @return character read from the input */ - const_iterator& operator++() + int get() { - assert(m_object != nullptr); + ++chars_read; + return (current = ia->get_character()); + } - switch (m_object->m_type) + /* + @brief read a number from the input + + @tparam T the type of the number + + @return number of type @a T + + @note This function needs to respect the system's endianess, because + bytes in CBOR and MessagePack are stored in network order (big + endian) and therefore need reordering on little endian systems. + + @throw parse_error.110 if input has less than `sizeof(T)` bytes + */ + template + T get_number() + { + // step 1: read input into array with system's byte order + std::array vec; + for (size_t i = 0; i < sizeof(T); ++i) { - case basic_json::value_t::object: - { - std::advance(m_it.object_iterator, 1); - break; - } + get(); + check_eof(); - case basic_json::value_t::array: + // reverse byte order prior to conversion if necessary + if (is_little_endian) { - std::advance(m_it.array_iterator, 1); - break; + vec[sizeof(T) - i - 1] = static_cast(current); } - - default: + else { - ++m_it.primitive_iterator; - break; + vec[i] = static_cast(current); } } - return *this; + // step 2: convert array into number of type T and return + T result; + std::memcpy(&result, vec.data(), sizeof(T)); + return result; } /*! - @brief post-decrement (it--) - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief create a string by reading characters from the input + + @param[in] len number of bytes to read + + @return string created by reading @a len bytes + + @throw parse_error.110 if input has less than @a len bytes */ - const_iterator operator--(int) + std::string get_string(const size_t len) { - auto result = *this; - --(*this); + std::string result; + for (size_t i = 0; i < len; ++i) + { + get(); + check_eof(); + result.append(1, static_cast(current)); + } return result; } /*! - @brief pre-decrement (--it) - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief reads a CBOR string + + This function first reads starting bytes to determine the expected + string length and then copies this number of bytes into a string. + Additionally, CBOR's strings with indefinite lengths are supported. + + @return string + + @throw parse_error.110 if input ended + @throw parse_error.113 if an unexpexted byte is read */ - const_iterator& operator--() + std::string get_cbor_string() { - assert(m_object != nullptr); + check_eof(); - switch (m_object->m_type) + switch (current) { - case basic_json::value_t::object: + // UTF-8 string (0x00..0x17 bytes follow) + case 0x60: + case 0x61: + case 0x62: + case 0x63: + case 0x64: + case 0x65: + case 0x66: + case 0x67: + case 0x68: + case 0x69: + case 0x6a: + case 0x6b: + case 0x6c: + case 0x6d: + case 0x6e: + case 0x6f: + case 0x70: + case 0x71: + case 0x72: + case 0x73: + case 0x74: + case 0x75: + case 0x76: + case 0x77: { - std::advance(m_it.object_iterator, -1); - break; + const auto len = static_cast(current & 0x1f); + return get_string(len); } - case basic_json::value_t::array: + case 0x78: // UTF-8 string (one-byte uint8_t for n follows) { - std::advance(m_it.array_iterator, -1); - break; + const auto len = static_cast(get_number()); + return get_string(len); } - default: + case 0x79: // UTF-8 string (two-byte uint16_t for n follow) { - --m_it.primitive_iterator; - break; + const auto len = static_cast(get_number()); + return get_string(len); } - } - - return *this; - } - - /*! - @brief comparison: equal - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - bool operator==(const const_iterator& other) const - { - // if objects are not the same, the comparison is undefined - if (m_object != other.m_object) - { - throw std::domain_error("cannot compare iterators of different containers"); - } - assert(m_object != nullptr); + case 0x7a: // UTF-8 string (four-byte uint32_t for n follow) + { + const auto len = static_cast(get_number()); + return get_string(len); + } - switch (m_object->m_type) - { - case basic_json::value_t::object: + case 0x7b: // UTF-8 string (eight-byte uint64_t for n follow) { - return (m_it.object_iterator == other.m_it.object_iterator); + const auto len = static_cast(get_number()); + return get_string(len); } - case basic_json::value_t::array: + case 0x7f: // UTF-8 string (indefinite length) { - return (m_it.array_iterator == other.m_it.array_iterator); + std::string result; + while (get() != 0xff) + { + check_eof(); + result.append(1, static_cast(current)); + } + return result; } default: { - return (m_it.primitive_iterator == other.m_it.primitive_iterator); + std::stringstream ss; + ss << std::setw(2) << std::setfill('0') << std::hex << current; + JSON_THROW(parse_error::create(113, chars_read, "expected a CBOR string; last byte: 0x" + ss.str())); } } } /*! - @brief comparison: not equal - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - bool operator!=(const const_iterator& other) const - { - return not operator==(other); - } + @brief reads a MessagePack string - /*! - @brief comparison: smaller - @pre The iterator is initialized; i.e. `m_object != nullptr`. + This function first reads starting bytes to determine the expected + string length and then copies this number of bytes into a string. + + @return string + + @throw parse_error.110 if input ended + @throw parse_error.113 if an unexpexted byte is read */ - bool operator<(const const_iterator& other) const + std::string get_msgpack_string() { - // if objects are not the same, the comparison is undefined - if (m_object != other.m_object) + check_eof(); + + switch (current) { - throw std::domain_error("cannot compare iterators of different containers"); - } + // fixstr + case 0xa0: + case 0xa1: + case 0xa2: + case 0xa3: + case 0xa4: + case 0xa5: + case 0xa6: + case 0xa7: + case 0xa8: + case 0xa9: + case 0xaa: + case 0xab: + case 0xac: + case 0xad: + case 0xae: + case 0xaf: + case 0xb0: + case 0xb1: + case 0xb2: + case 0xb3: + case 0xb4: + case 0xb5: + case 0xb6: + case 0xb7: + case 0xb8: + case 0xb9: + case 0xba: + case 0xbb: + case 0xbc: + case 0xbd: + case 0xbe: + case 0xbf: + { + const auto len = static_cast(current & 0x1f); + return get_string(len); + } - assert(m_object != nullptr); + case 0xd9: // str 8 + { + const auto len = static_cast(get_number()); + return get_string(len); + } - switch (m_object->m_type) - { - case basic_json::value_t::object: + case 0xda: // str 16 { - throw std::domain_error("cannot compare order of object iterators"); + const auto len = static_cast(get_number()); + return get_string(len); } - case basic_json::value_t::array: + case 0xdb: // str 32 { - return (m_it.array_iterator < other.m_it.array_iterator); + const auto len = static_cast(get_number()); + return get_string(len); } default: { - return (m_it.primitive_iterator < other.m_it.primitive_iterator); + std::stringstream ss; + ss << std::setw(2) << std::setfill('0') << std::hex << current; + JSON_THROW(parse_error::create(113, chars_read, "expected a MessagePack string; last byte: 0x" + ss.str())); } } } /*! - @brief comparison: less than or equal - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief check if input ended + @throw parse_error.110 if input ended */ - bool operator<=(const const_iterator& other) const + void check_eof() const { - return not other.operator < (*this); + if (JSON_UNLIKELY(current == std::char_traits::eof())) + { + JSON_THROW(parse_error::create(110, chars_read, "unexpected end of input")); + } } - /*! - @brief comparison: greater than - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - bool operator>(const const_iterator& other) const - { - return not operator<=(other); - } + private: + /// input adapter + input_adapter_t ia = nullptr; + + /// the current character + int current = std::char_traits::eof(); + + /// the number of characters read + size_t chars_read = 0; + /// whether we can assume little endianess + const bool is_little_endian = true; + }; + + /*! + @brief serialization to CBOR and MessagePack values + */ + class binary_writer + { + public: /*! - @brief comparison: greater than or equal - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief create a binary writer + + @param[in] adapter output adapter to write to */ - bool operator>=(const const_iterator& other) const + explicit binary_writer(output_adapter_t adapter) + : is_little_endian(binary_reader::little_endianess()), oa(adapter) { - return not operator<(other); + assert(oa); } /*! - @brief add to iterator - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief[in] j JSON value to serialize */ - const_iterator& operator+=(difference_type i) + void write_cbor(const basic_json& j) { - assert(m_object != nullptr); - - switch (m_object->m_type) + switch (j.type()) { - case basic_json::value_t::object: + case value_t::null: + { + oa->write_character(0xf6); + break; + } + + case value_t::boolean: + { + oa->write_character(j.m_value.boolean ? 0xf5 : 0xf4); + break; + } + + case value_t::number_integer: { - throw std::domain_error("cannot use offsets with object iterators"); + if (j.m_value.number_integer >= 0) + { + // CBOR does not differentiate between positive signed + // integers and unsigned integers. Therefore, we used the + // code from the value_t::number_unsigned case here. + if (j.m_value.number_integer <= 0x17) + { + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits::max)()) + { + oa->write_character(0x18); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits::max)()) + { + oa->write_character(0x19); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits::max)()) + { + oa->write_character(0x1a); + write_number(static_cast(j.m_value.number_integer)); + } + else + { + oa->write_character(0x1b); + write_number(static_cast(j.m_value.number_integer)); + } + } + else + { + // The conversions below encode the sign in the first + // byte, and the value is converted to a positive number. + const auto positive_number = -1 - j.m_value.number_integer; + if (j.m_value.number_integer >= -24) + { + write_number(static_cast(0x20 + positive_number)); + } + else if (positive_number <= (std::numeric_limits::max)()) + { + oa->write_character(0x38); + write_number(static_cast(positive_number)); + } + else if (positive_number <= (std::numeric_limits::max)()) + { + oa->write_character(0x39); + write_number(static_cast(positive_number)); + } + else if (positive_number <= (std::numeric_limits::max)()) + { + oa->write_character(0x3a); + write_number(static_cast(positive_number)); + } + else + { + oa->write_character(0x3b); + write_number(static_cast(positive_number)); + } + } + break; } - case basic_json::value_t::array: + case value_t::number_unsigned: { - std::advance(m_it.array_iterator, i); + if (j.m_value.number_unsigned <= 0x17) + { + write_number(static_cast(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + oa->write_character(0x18); + write_number(static_cast(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + oa->write_character(0x19); + write_number(static_cast(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + oa->write_character(0x1a); + write_number(static_cast(j.m_value.number_unsigned)); + } + else + { + oa->write_character(0x1b); + write_number(static_cast(j.m_value.number_unsigned)); + } break; } - default: + case value_t::number_float: { - m_it.primitive_iterator += i; + // Double-Precision Float + oa->write_character(0xfb); + write_number(j.m_value.number_float); break; } - } - - return *this; - } - - /*! - @brief subtract from iterator - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - const_iterator& operator-=(difference_type i) - { - return operator+=(-i); - } - /*! - @brief add to iterator - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - const_iterator operator+(difference_type i) - { - auto result = *this; - result += i; - return result; - } - - /*! - @brief subtract from iterator - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - const_iterator operator-(difference_type i) - { - auto result = *this; - result -= i; - return result; - } + case value_t::string: + { + // step 1: write control byte and the string length + const auto N = j.m_value.string->size(); + if (N <= 0x17) + { + write_number(static_cast(0x60 + N)); + } + else if (N <= 0xff) + { + oa->write_character(0x78); + write_number(static_cast(N)); + } + else if (N <= 0xffff) + { + oa->write_character(0x79); + write_number(static_cast(N)); + } + else if (N <= 0xffffffff) + { + oa->write_character(0x7a); + write_number(static_cast(N)); + } + // LCOV_EXCL_START + else if (N <= 0xffffffffffffffff) + { + oa->write_character(0x7b); + write_number(static_cast(N)); + } + // LCOV_EXCL_STOP - /*! - @brief return difference - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - difference_type operator-(const const_iterator& other) const - { - assert(m_object != nullptr); + // step 2: write the string + oa->write_characters(reinterpret_cast(j.m_value.string->c_str()), + j.m_value.string->size()); + break; + } - switch (m_object->m_type) - { - case basic_json::value_t::object: + case value_t::array: { - throw std::domain_error("cannot use offsets with object iterators"); + // step 1: write control byte and the array size + const auto N = j.m_value.array->size(); + if (N <= 0x17) + { + write_number(static_cast(0x80 + N)); + } + else if (N <= 0xff) + { + oa->write_character(0x98); + write_number(static_cast(N)); + } + else if (N <= 0xffff) + { + oa->write_character(0x99); + write_number(static_cast(N)); + } + else if (N <= 0xffffffff) + { + oa->write_character(0x9a); + write_number(static_cast(N)); + } + // LCOV_EXCL_START + else if (N <= 0xffffffffffffffff) + { + oa->write_character(0x9b); + write_number(static_cast(N)); + } + // LCOV_EXCL_STOP + + // step 2: write each element + for (const auto& el : *j.m_value.array) + { + write_cbor(el); + } + break; } - case basic_json::value_t::array: + case value_t::object: { - return m_it.array_iterator - other.m_it.array_iterator; + // step 1: write control byte and the object size + const auto N = j.m_value.object->size(); + if (N <= 0x17) + { + write_number(static_cast(0xa0 + N)); + } + else if (N <= 0xff) + { + oa->write_character(0xb8); + write_number(static_cast(N)); + } + else if (N <= 0xffff) + { + oa->write_character(0xb9); + write_number(static_cast(N)); + } + else if (N <= 0xffffffff) + { + oa->write_character(0xba); + write_number(static_cast(N)); + } + // LCOV_EXCL_START + else if (N <= 0xffffffffffffffff) + { + oa->write_character(0xbb); + write_number(static_cast(N)); + } + // LCOV_EXCL_STOP + + // step 2: write each element + for (const auto& el : *j.m_value.object) + { + write_cbor(el.first); + write_cbor(el.second); + } + break; } default: { - return m_it.primitive_iterator - other.m_it.primitive_iterator; + break; } } } /*! - @brief access to successor - @pre The iterator is initialized; i.e. `m_object != nullptr`. + @brief[in] j JSON value to serialize */ - reference operator[](difference_type n) const + void write_msgpack(const basic_json& j) { - assert(m_object != nullptr); - - switch (m_object->m_type) + switch (j.type()) { - case basic_json::value_t::object: + case value_t::null: { - throw std::domain_error("cannot use operator[] for object iterators"); + // nil + oa->write_character(0xc0); + break; } - case basic_json::value_t::array: + case value_t::boolean: { - return *std::next(m_it.array_iterator, n); + // true and false + oa->write_character(j.m_value.boolean ? 0xc3 : 0xc2); + break; } - case basic_json::value_t::null: + case value_t::number_integer: { - throw std::out_of_range("cannot get value"); + if (j.m_value.number_integer >= 0) + { + // MessagePack does not differentiate between positive + // signed integers and unsigned integers. Therefore, we + // used the code from the value_t::number_unsigned case + // here. + if (j.m_value.number_unsigned < 128) + { + // positive fixnum + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + // uint 8 + oa->write_character(0xcc); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + // uint 16 + oa->write_character(0xcd); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + // uint 32 + oa->write_character(0xce); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + // uint 64 + oa->write_character(0xcf); + write_number(static_cast(j.m_value.number_integer)); + } + } + else + { + if (j.m_value.number_integer >= -32) + { + // negative fixnum + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits::min)() and j.m_value.number_integer <= (std::numeric_limits::max)()) + { + // int 8 + oa->write_character(0xd0); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits::min)() and j.m_value.number_integer <= (std::numeric_limits::max)()) + { + // int 16 + oa->write_character(0xd1); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits::min)() and j.m_value.number_integer <= (std::numeric_limits::max)()) + { + // int 32 + oa->write_character(0xd2); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits::min)() and j.m_value.number_integer <= (std::numeric_limits::max)()) + { + // int 64 + oa->write_character(0xd3); + write_number(static_cast(j.m_value.number_integer)); + } + } + break; } - default: + case value_t::number_unsigned: { - if (m_it.primitive_iterator == -n) + if (j.m_value.number_unsigned < 128) { - return *m_object; + // positive fixnum + write_number(static_cast(j.m_value.number_integer)); } - else + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + // uint 8 + oa->write_character(0xcc); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + // uint 16 + oa->write_character(0xcd); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) + { + // uint 32 + oa->write_character(0xce); + write_number(static_cast(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits::max)()) { - throw std::out_of_range("cannot get value"); + // uint 64 + oa->write_character(0xcf); + write_number(static_cast(j.m_value.number_integer)); } + break; } - } - } - - /*! - @brief return the key of an object iterator - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - typename object_t::key_type key() const - { - assert(m_object != nullptr); - - if (m_object->is_object()) - { - return m_it.object_iterator->first; - } - else - { - throw std::domain_error("cannot use key() for non-object iterators"); - } - } - - /*! - @brief return the value of an iterator - @pre The iterator is initialized; i.e. `m_object != nullptr`. - */ - reference value() const - { - return operator*(); - } - - private: - /// associated JSON instance - pointer m_object = nullptr; - /// the actual iterator of the associated instance - internal_iterator m_it = internal_iterator(); - }; - - /*! - @brief a mutable random access iterator for the @ref basic_json class - - @requirement The class satisfies the following concept requirements: - - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator): - The iterator that can be moved to point (forward and backward) to any - element in constant time. - - [OutputIterator](http://en.cppreference.com/w/cpp/concept/OutputIterator): - It is possible to write to the pointed-to element. - - @since version 1.0.0 - */ - class iterator : public const_iterator - { - public: - using base_iterator = const_iterator; - using pointer = typename basic_json::pointer; - using reference = typename basic_json::reference; - /// default constructor - iterator() = default; - - /// constructor for a given JSON instance - explicit iterator(pointer object) noexcept - : base_iterator(object) - {} - - /// copy constructor - iterator(const iterator& other) noexcept - : base_iterator(other) - {} - - /// copy assignment - iterator& operator=(iterator other) noexcept( - std::is_nothrow_move_constructible::value and - std::is_nothrow_move_assignable::value and - std::is_nothrow_move_constructible::value and - std::is_nothrow_move_assignable::value - ) - { - base_iterator::operator=(other); - return *this; - } + case value_t::number_float: + { + // float 64 + oa->write_character(0xcb); + write_number(j.m_value.number_float); + break; + } - /// return a reference to the value pointed to by the iterator - reference operator*() const - { - return const_cast(base_iterator::operator*()); - } + case value_t::string: + { + // step 1: write control byte and the string length + const auto N = j.m_value.string->size(); + if (N <= 31) + { + // fixstr + write_number(static_cast(0xa0 | N)); + } + else if (N <= 255) + { + // str 8 + oa->write_character(0xd9); + write_number(static_cast(N)); + } + else if (N <= 65535) + { + // str 16 + oa->write_character(0xda); + write_number(static_cast(N)); + } + else if (N <= 4294967295) + { + // str 32 + oa->write_character(0xdb); + write_number(static_cast(N)); + } - /// dereference the iterator - pointer operator->() const - { - return const_cast(base_iterator::operator->()); - } + // step 2: write the string + oa->write_characters(reinterpret_cast(j.m_value.string->c_str()), + j.m_value.string->size()); + break; + } - /// post-increment (it++) - iterator operator++(int) - { - iterator result = *this; - base_iterator::operator++(); - return result; - } + case value_t::array: + { + // step 1: write control byte and the array size + const auto N = j.m_value.array->size(); + if (N <= 15) + { + // fixarray + write_number(static_cast(0x90 | N)); + } + else if (N <= 0xffff) + { + // array 16 + oa->write_character(0xdc); + write_number(static_cast(N)); + } + else if (N <= 0xffffffff) + { + // array 32 + oa->write_character(0xdd); + write_number(static_cast(N)); + } - /// pre-increment (++it) - iterator& operator++() - { - base_iterator::operator++(); - return *this; - } + // step 2: write each element + for (const auto& el : *j.m_value.array) + { + write_msgpack(el); + } + break; + } - /// post-decrement (it--) - iterator operator--(int) - { - iterator result = *this; - base_iterator::operator--(); - return result; - } + case value_t::object: + { + // step 1: write control byte and the object size + const auto N = j.m_value.object->size(); + if (N <= 15) + { + // fixmap + write_number(static_cast(0x80 | (N & 0xf))); + } + else if (N <= 65535) + { + // map 16 + oa->write_character(0xde); + write_number(static_cast(N)); + } + else if (N <= 4294967295) + { + // map 32 + oa->write_character(0xdf); + write_number(static_cast(N)); + } - /// pre-decrement (--it) - iterator& operator--() - { - base_iterator::operator--(); - return *this; - } + // step 2: write each element + for (const auto& el : *j.m_value.object) + { + write_msgpack(el.first); + write_msgpack(el.second); + } + break; + } - /// add to iterator - iterator& operator+=(difference_type i) - { - base_iterator::operator+=(i); - return *this; + default: + { + break; + } + } } - /// subtract from iterator - iterator& operator-=(difference_type i) - { - base_iterator::operator-=(i); - return *this; - } + private: + /* + @brief write a number to output input - /// add to iterator - iterator operator+(difference_type i) - { - auto result = *this; - result += i; - return result; - } + @param[in] n number of type @a T + @tparam T the type of the number - /// subtract from iterator - iterator operator-(difference_type i) + @note This function needs to respect the system's endianess, because + bytes in CBOR and MessagePack are stored in network order (big + endian) and therefore need reordering on little endian systems. + */ + template + void write_number(T n) { - auto result = *this; - result -= i; - return result; - } + // step 1: write number to array of length T + std::array vec; + std::memcpy(vec.data(), &n, sizeof(T)); - /// return difference - difference_type operator-(const iterator& other) const - { - return base_iterator::operator-(other); + // step 2: write array to output (with possible reordering) + for (size_t i = 0; i < sizeof(T); ++i) + { + // reverse byte order prior to conversion if necessary + if (is_little_endian) + { + oa->write_character(vec[sizeof(T) - i - 1]); + } + else + { + oa->write_character(vec[i]); + } + } } - /// access to successor - reference operator[](difference_type n) const - { - return const_cast(base_iterator::operator[](n)); - } + private: + /// whether we can assume little endianess + const bool is_little_endian = true; - /// return the value of an iterator - reference value() const - { - return const_cast(base_iterator::value()); - } + /// the output + output_adapter_t oa = nullptr; }; + public: /*! - @brief a template for a reverse iterator class - - @tparam Base the base iterator type to reverse. Valid types are @ref - iterator (to create @ref reverse_iterator) and @ref const_iterator (to - create @ref const_reverse_iterator). + @brief create a CBOR serialization of a given JSON value + + Serializes a given JSON value @a j to a byte vector using the CBOR (Concise + Binary Object Representation) serialization format. CBOR is a binary + serialization format which aims to be more compact than JSON itself, yet + more efficient to parse. + + The library uses the following mapping from JSON values types to + CBOR types according to the CBOR specification (RFC 7049): + + JSON value type | value/range | CBOR type | first byte + --------------- | ------------------------------------------ | ---------------------------------- | --------------- + null | `null` | Null | 0xf6 + boolean | `true` | True | 0xf5 + boolean | `false` | False | 0xf4 + number_integer | -9223372036854775808..-2147483649 | Negative integer (8 bytes follow) | 0x3b + number_integer | -2147483648..-32769 | Negative integer (4 bytes follow) | 0x3a + number_integer | -32768..-129 | Negative integer (2 bytes follow) | 0x39 + number_integer | -128..-25 | Negative integer (1 byte follow) | 0x38 + number_integer | -24..-1 | Negative integer | 0x20..0x37 + number_integer | 0..23 | Integer | 0x00..0x17 + number_integer | 24..255 | Unsigned integer (1 byte follow) | 0x18 + number_integer | 256..65535 | Unsigned integer (2 bytes follow) | 0x19 + number_integer | 65536..4294967295 | Unsigned integer (4 bytes follow) | 0x1a + number_integer | 4294967296..18446744073709551615 | Unsigned integer (8 bytes follow) | 0x1b + number_unsigned | 0..23 | Integer | 0x00..0x17 + number_unsigned | 24..255 | Unsigned integer (1 byte follow) | 0x18 + number_unsigned | 256..65535 | Unsigned integer (2 bytes follow) | 0x19 + number_unsigned | 65536..4294967295 | Unsigned integer (4 bytes follow) | 0x1a + number_unsigned | 4294967296..18446744073709551615 | Unsigned integer (8 bytes follow) | 0x1b + number_float | *any value* | Double-Precision Float | 0xfb + string | *length*: 0..23 | UTF-8 string | 0x60..0x77 + string | *length*: 23..255 | UTF-8 string (1 byte follow) | 0x78 + string | *length*: 256..65535 | UTF-8 string (2 bytes follow) | 0x79 + string | *length*: 65536..4294967295 | UTF-8 string (4 bytes follow) | 0x7a + string | *length*: 4294967296..18446744073709551615 | UTF-8 string (8 bytes follow) | 0x7b + array | *size*: 0..23 | array | 0x80..0x97 + array | *size*: 23..255 | array (1 byte follow) | 0x98 + array | *size*: 256..65535 | array (2 bytes follow) | 0x99 + array | *size*: 65536..4294967295 | array (4 bytes follow) | 0x9a + array | *size*: 4294967296..18446744073709551615 | array (8 bytes follow) | 0x9b + object | *size*: 0..23 | map | 0xa0..0xb7 + object | *size*: 23..255 | map (1 byte follow) | 0xb8 + object | *size*: 256..65535 | map (2 bytes follow) | 0xb9 + object | *size*: 65536..4294967295 | map (4 bytes follow) | 0xba + object | *size*: 4294967296..18446744073709551615 | map (8 bytes follow) | 0xbb + + @note The mapping is **complete** in the sense that any JSON value type + can be converted to a CBOR value. + + @note The following CBOR types are not used in the conversion: + - byte strings (0x40..0x5f) + - UTF-8 strings terminated by "break" (0x7f) + - arrays terminated by "break" (0x9f) + - maps terminated by "break" (0xbf) + - date/time (0xc0..0xc1) + - bignum (0xc2..0xc3) + - decimal fraction (0xc4) + - bigfloat (0xc5) + - tagged items (0xc6..0xd4, 0xd8..0xdb) + - expected conversions (0xd5..0xd7) + - simple values (0xe0..0xf3, 0xf8) + - undefined (0xf7) + - half and single-precision floats (0xf9-0xfa) + - break (0xff) - @requirement The class satisfies the following concept requirements: - - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator): - The iterator that can be moved to point (forward and backward) to any - element in constant time. - - [OutputIterator](http://en.cppreference.com/w/cpp/concept/OutputIterator): - It is possible to write to the pointed-to element (only if @a Base is - @ref iterator). + @param[in] j JSON value to serialize + @return MessagePack serialization as byte vector - @since version 1.0.0 - */ - template - class json_reverse_iterator : public std::reverse_iterator - { - public: - /// shortcut to the reverse iterator adaptor - using base_iterator = std::reverse_iterator; - /// the reference type for the pointed-to element - using reference = typename Base::reference; + @complexity Linear in the size of the JSON value @a j. - /// create reverse iterator from iterator - json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept - : base_iterator(it) - {} + @liveexample{The example shows the serialization of a JSON value to a byte + vector in CBOR format.,to_cbor} - /// create reverse iterator from base class - json_reverse_iterator(const base_iterator& it) noexcept - : base_iterator(it) - {} + @sa http://cbor.io + @sa @ref from_cbor(const std::vector&, const size_t) for the + analogous deserialization + @sa @ref to_msgpack(const basic_json& for the related MessagePack format - /// post-increment (it++) - json_reverse_iterator operator++(int) - { - return base_iterator::operator++(1); - } + @since version 2.0.9 + */ + static std::vector to_cbor(const basic_json& j) + { + std::vector result; + binary_writer bw(output_adapter::create(result)); + bw.write_cbor(j); + return result; + } - /// pre-increment (++it) - json_reverse_iterator& operator++() - { - base_iterator::operator++(); - return *this; - } + /*! + @brief create a MessagePack serialization of a given JSON value + + Serializes a given JSON value @a j to a byte vector using the MessagePack + serialization format. MessagePack is a binary serialization format which + aims to be more compact than JSON itself, yet more efficient to parse. + + The library uses the following mapping from JSON values types to + MessagePack types according to the MessagePack specification: + + JSON value type | value/range | MessagePack type | first byte + --------------- | --------------------------------- | ---------------- | ---------- + null | `null` | nil | 0xc0 + boolean | `true` | true | 0xc3 + boolean | `false` | false | 0xc2 + number_integer | -9223372036854775808..-2147483649 | int64 | 0xd3 + number_integer | -2147483648..-32769 | int32 | 0xd2 + number_integer | -32768..-129 | int16 | 0xd1 + number_integer | -128..-33 | int8 | 0xd0 + number_integer | -32..-1 | negative fixint | 0xe0..0xff + number_integer | 0..127 | positive fixint | 0x00..0x7f + number_integer | 128..255 | uint 8 | 0xcc + number_integer | 256..65535 | uint 16 | 0xcd + number_integer | 65536..4294967295 | uint 32 | 0xce + number_integer | 4294967296..18446744073709551615 | uint 64 | 0xcf + number_unsigned | 0..127 | positive fixint | 0x00..0x7f + number_unsigned | 128..255 | uint 8 | 0xcc + number_unsigned | 256..65535 | uint 16 | 0xcd + number_unsigned | 65536..4294967295 | uint 32 | 0xce + number_unsigned | 4294967296..18446744073709551615 | uint 64 | 0xcf + number_float | *any value* | float 64 | 0xcb + string | *length*: 0..31 | fixstr | 0xa0..0xbf + string | *length*: 32..255 | str 8 | 0xd9 + string | *length*: 256..65535 | str 16 | 0xda + string | *length*: 65536..4294967295 | str 32 | 0xdb + array | *size*: 0..15 | fixarray | 0x90..0x9f + array | *size*: 16..65535 | array 16 | 0xdc + array | *size*: 65536..4294967295 | array 32 | 0xdd + object | *size*: 0..15 | fix map | 0x80..0x8f + object | *size*: 16..65535 | map 16 | 0xde + object | *size*: 65536..4294967295 | map 32 | 0xdf + + @note The mapping is **complete** in the sense that any JSON value type + can be converted to a MessagePack value. + + @note The following values can **not** be converted to a MessagePack value: + - strings with more than 4294967295 bytes + - arrays with more than 4294967295 elements + - objects with more than 4294967295 elements + + @note The following MessagePack types are not used in the conversion: + - bin 8 - bin 32 (0xc4..0xc6) + - ext 8 - ext 32 (0xc7..0xc9) + - float 32 (0xca) + - fixext 1 - fixext 16 (0xd4..0xd8) + + @note Any MessagePack output created @ref to_msgpack can be successfully + parsed by @ref from_msgpack. - /// post-decrement (it--) - json_reverse_iterator operator--(int) - { - return base_iterator::operator--(1); - } + @param[in] j JSON value to serialize + @return MessagePack serialization as byte vector - /// pre-decrement (--it) - json_reverse_iterator& operator--() - { - base_iterator::operator--(); - return *this; - } + @complexity Linear in the size of the JSON value @a j. - /// add to iterator - json_reverse_iterator& operator+=(difference_type i) - { - base_iterator::operator+=(i); - return *this; - } + @liveexample{The example shows the serialization of a JSON value to a byte + vector in MessagePack format.,to_msgpack} - /// add to iterator - json_reverse_iterator operator+(difference_type i) const - { - auto result = *this; - result += i; - return result; - } + @sa http://msgpack.org + @sa @ref from_msgpack(const std::vector&, const size_t) for the + analogous deserialization + @sa @ref to_cbor(const basic_json& for the related CBOR format - /// subtract from iterator - json_reverse_iterator operator-(difference_type i) const - { - auto result = *this; - result -= i; - return result; - } + @since version 2.0.9 + */ + static std::vector to_msgpack(const basic_json& j) + { + std::vector result; + binary_writer bw(output_adapter::create(result)); + bw.write_msgpack(j); + return result; + } - /// return difference - difference_type operator-(const json_reverse_iterator& other) const - { - return this->base() - other.base(); - } + /*! + @brief create a JSON value from a byte vector in CBOR format + + Deserializes a given byte vector @a v to a JSON value using the CBOR + (Concise Binary Object Representation) serialization format. + + The library maps CBOR types to JSON value types as follows: + + CBOR type | JSON value type | first byte + ---------------------- | --------------- | ---------- + Integer | number_unsigned | 0x00..0x17 + Unsigned integer | number_unsigned | 0x18 + Unsigned integer | number_unsigned | 0x19 + Unsigned integer | number_unsigned | 0x1a + Unsigned integer | number_unsigned | 0x1b + Negative integer | number_integer | 0x20..0x37 + Negative integer | number_integer | 0x38 + Negative integer | number_integer | 0x39 + Negative integer | number_integer | 0x3a + Negative integer | number_integer | 0x3b + Negative integer | number_integer | 0x40..0x57 + UTF-8 string | string | 0x60..0x77 + UTF-8 string | string | 0x78 + UTF-8 string | string | 0x79 + UTF-8 string | string | 0x7a + UTF-8 string | string | 0x7b + UTF-8 string | string | 0x7f + array | array | 0x80..0x97 + array | array | 0x98 + array | array | 0x99 + array | array | 0x9a + array | array | 0x9b + array | array | 0x9f + map | object | 0xa0..0xb7 + map | object | 0xb8 + map | object | 0xb9 + map | object | 0xba + map | object | 0xbb + map | object | 0xbf + False | `false` | 0xf4 + True | `true` | 0xf5 + Nill | `null` | 0xf6 + Half-Precision Float | number_float | 0xf9 + Single-Precision Float | number_float | 0xfa + Double-Precision Float | number_float | 0xfb + + @warning The mapping is **incomplete** in the sense that not all CBOR + types can be converted to a JSON value. The following CBOR types + are not supported and will yield parse errors (parse_error.112): + - byte strings (0x40..0x5f) + - date/time (0xc0..0xc1) + - bignum (0xc2..0xc3) + - decimal fraction (0xc4) + - bigfloat (0xc5) + - tagged items (0xc6..0xd4, 0xd8..0xdb) + - expected conversions (0xd5..0xd7) + - simple values (0xe0..0xf3, 0xf8) + - undefined (0xf7) + + @warning CBOR allows map keys of any type, whereas JSON only allows + strings as keys in object values. Therefore, CBOR maps with keys + other than UTF-8 strings are rejected (parse_error.113). + + @note Any CBOR output created @ref to_cbor can be successfully parsed by + @ref from_cbor. + + @param[in] v a byte vector in CBOR format + @param[in] start_index the index to start reading from @a v (0 by default) + @return deserialized JSON value + + @throw parse_error.110 if the given vector ends prematurely + @throw parse_error.112 if unsupported features from CBOR were + used in the given vector @a v or if the input is not valid CBOR + @throw parse_error.113 if a string was expected as map key, but not found + + @complexity Linear in the size of the byte vector @a v. + + @liveexample{The example shows the deserialization of a byte vector in CBOR + format to a JSON value.,from_cbor} + + @sa http://cbor.io + @sa @ref to_cbor(const basic_json&) for the analogous serialization + @sa @ref from_msgpack(const std::vector&, const size_t) for the + related MessagePack format + + @since version 2.0.9, parameter @a start_index since 2.1.1 + */ + static basic_json from_cbor(const std::vector& v, + const size_t start_index = 0) + { + binary_reader br(input_adapter::create(v.begin() + static_cast(start_index), v.end())); + return br.parse_cbor(); + } + + + /*! + @brief create a JSON value from a byte vector in MessagePack format + + Deserializes a given byte vector @a v to a JSON value using the MessagePack + serialization format. + + The library maps MessagePack types to JSON value types as follows: + + MessagePack type | JSON value type | first byte + ---------------- | --------------- | ---------- + positive fixint | number_unsigned | 0x00..0x7f + fixmap | object | 0x80..0x8f + fixarray | array | 0x90..0x9f + fixstr | string | 0xa0..0xbf + nil | `null` | 0xc0 + false | `false` | 0xc2 + true | `true` | 0xc3 + float 32 | number_float | 0xca + float 64 | number_float | 0xcb + uint 8 | number_unsigned | 0xcc + uint 16 | number_unsigned | 0xcd + uint 32 | number_unsigned | 0xce + uint 64 | number_unsigned | 0xcf + int 8 | number_integer | 0xd0 + int 16 | number_integer | 0xd1 + int 32 | number_integer | 0xd2 + int 64 | number_integer | 0xd3 + str 8 | string | 0xd9 + str 16 | string | 0xda + str 32 | string | 0xdb + array 16 | array | 0xdc + array 32 | array | 0xdd + map 16 | object | 0xde + map 32 | object | 0xdf + negative fixint | number_integer | 0xe0-0xff + + @warning The mapping is **incomplete** in the sense that not all + MessagePack types can be converted to a JSON value. The following + MessagePack types are not supported and will yield parse errors: + - bin 8 - bin 32 (0xc4..0xc6) + - ext 8 - ext 32 (0xc7..0xc9) + - fixext 1 - fixext 16 (0xd4..0xd8) + + @note Any MessagePack output created @ref to_msgpack can be successfully + parsed by @ref from_msgpack. + + @param[in] v a byte vector in MessagePack format + @param[in] start_index the index to start reading from @a v (0 by default) + @return deserialized JSON value + + @throw parse_error.110 if the given vector ends prematurely + @throw parse_error.112 if unsupported features from MessagePack were + used in the given vector @a v or if the input is not valid MessagePack + @throw parse_error.113 if a string was expected as map key, but not found + + @complexity Linear in the size of the byte vector @a v. - /// access to successor - reference operator[](difference_type n) const - { - return *(this->operator+(n)); - } + @liveexample{The example shows the deserialization of a byte vector in + MessagePack format to a JSON value.,from_msgpack} - /// return the key of an object iterator - typename object_t::key_type key() const - { - auto it = --this->base(); - return it.key(); - } + @sa http://msgpack.org + @sa @ref to_msgpack(const basic_json&) for the analogous serialization + @sa @ref from_cbor(const std::vector&, const size_t) for the + related CBOR format - /// return the value of an iterator - reference value() const - { - auto it = --this->base(); - return it.operator * (); - } - }; + @since version 2.0.9, parameter @a start_index since 2.1.1 + */ + static basic_json from_msgpack(const std::vector& v, + const size_t start_index = 0) + { + binary_reader br(input_adapter::create(v.begin() + static_cast(start_index), v.end())); + return br.parse_msgpack(); + } + /// @} - private: ////////////////////// // lexer and parser // ////////////////////// + private: /*! @brief lexical analysis - This class organizes the lexical analysis during JSON deserialization. The - core of it is a scanner generated by [re2c](http://re2c.org) that - processes a buffer and recognizes tokens according to RFC 7159. + This class organizes the lexical analysis during JSON deserialization. */ class lexer { public: - /// token types for the parser - enum class token_type - { - uninitialized, ///< indicating the scanner is uninitialized - literal_true, ///< the `true` literal - literal_false, ///< the `false` literal - literal_null, ///< the `null` literal - value_string, ///< a string -- use get_string() for actual value - value_number, ///< a number -- use get_number() for actual value - begin_array, ///< the character for array begin `[` - begin_object, ///< the character for object begin `{` - end_array, ///< the character for array end `]` - end_object, ///< the character for object end `}` - name_separator, ///< the name separator `:` - value_separator, ///< the value separator `,` - parse_error, ///< indicating a parse error - end_of_input ///< indicating the end of the input buffer - }; - - /// the char type to use in the lexer - using lexer_char_t = unsigned char; - - /// a lexer from a buffer with given length - lexer(const lexer_char_t* buff, const size_t len) noexcept - : m_content(buff) - { - assert(m_content != nullptr); - m_start = m_cursor = m_content; - m_limit = m_content + len; - } - - /// a lexer from an input stream - explicit lexer(std::istream& s) - : m_stream(&s), m_line_buffer() - { - // immediately abort if stream is erroneous - if (s.fail()) - { - throw std::invalid_argument("stream error: " + std::string(strerror(errno))); - } - - // fill buffer - fill_line_buffer(); - - // skip UTF-8 byte-order mark - if (m_line_buffer.size() >= 3 and m_line_buffer.substr(0, 3) == "\xEF\xBB\xBF") - { - m_line_buffer[0] = ' '; - m_line_buffer[1] = ' '; - m_line_buffer[2] = ' '; - } - } - - // switch off unwanted functions (due to pointer members) - lexer() = delete; - lexer(const lexer&) = delete; - lexer operator=(const lexer&) = delete; - - /*! - @brief create a string from one or two Unicode code points - - There are two cases: (1) @a codepoint1 is in the Basic Multilingual - Plane (U+0000 through U+FFFF) and @a codepoint2 is 0, or (2) - @a codepoint1 and @a codepoint2 are a UTF-16 surrogate pair to - represent a code point above U+FFFF. - - @param[in] codepoint1 the code point (can be high surrogate) - @param[in] codepoint2 the code point (can be low surrogate or 0) - - @return string representation of the code point; the length of the - result string is between 1 and 4 characters. - - @throw std::out_of_range if code point is > 0x10ffff; example: `"code - points above 0x10FFFF are invalid"` - @throw std::invalid_argument if the low surrogate is invalid; example: - `""missing or wrong low surrogate""` - - @complexity Constant. - - @see - */ - static string_t to_unicode(const std::size_t codepoint1, - const std::size_t codepoint2 = 0) - { - // calculate the code point from the given code points - std::size_t codepoint = codepoint1; - - // check if codepoint1 is a high surrogate - if (codepoint1 >= 0xD800 and codepoint1 <= 0xDBFF) - { - // check if codepoint2 is a low surrogate - if (codepoint2 >= 0xDC00 and codepoint2 <= 0xDFFF) - { - codepoint = - // high surrogate occupies the most significant 22 bits - (codepoint1 << 10) - // low surrogate occupies the least significant 15 bits - + codepoint2 - // there is still the 0xD800, 0xDC00 and 0x10000 noise - // in the result so we have to subtract with: - // (0xD800 << 10) + DC00 - 0x10000 = 0x35FDC00 - - 0x35FDC00; - } - else - { - throw std::invalid_argument("missing or wrong low surrogate"); - } - } - - string_t result; - - if (codepoint < 0x80) - { - // 1-byte characters: 0xxxxxxx (ASCII) - result.append(1, static_cast(codepoint)); - } - else if (codepoint <= 0x7ff) - { - // 2-byte characters: 110xxxxx 10xxxxxx - result.append(1, static_cast(0xC0 | ((codepoint >> 6) & 0x1F))); - result.append(1, static_cast(0x80 | (codepoint & 0x3F))); - } - else if (codepoint <= 0xffff) - { - // 3-byte characters: 1110xxxx 10xxxxxx 10xxxxxx - result.append(1, static_cast(0xE0 | ((codepoint >> 12) & 0x0F))); - result.append(1, static_cast(0x80 | ((codepoint >> 6) & 0x3F))); - result.append(1, static_cast(0x80 | (codepoint & 0x3F))); - } - else if (codepoint <= 0x10ffff) - { - // 4-byte characters: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx - result.append(1, static_cast(0xF0 | ((codepoint >> 18) & 0x07))); - result.append(1, static_cast(0x80 | ((codepoint >> 12) & 0x3F))); - result.append(1, static_cast(0x80 | ((codepoint >> 6) & 0x3F))); - result.append(1, static_cast(0x80 | (codepoint & 0x3F))); - } - else - { - throw std::out_of_range("code points above 0x10FFFF are invalid"); - } - - return result; - } + /// token types for the parser + enum class token_type + { + uninitialized, ///< indicating the scanner is uninitialized + literal_true, ///< the `true` literal + literal_false, ///< the `false` literal + literal_null, ///< the `null` literal + value_string, ///< a string -- use get_string() for actual value + value_unsigned, ///< an unsigned integer -- use get_number_unsigned() for actual value + value_integer, ///< a signed integer -- use get_number_integer() for actual value + value_float, ///< an floating point number -- use get_number_float() for actual value + begin_array, ///< the character for array begin `[` + begin_object, ///< the character for object begin `{` + end_array, ///< the character for array end `]` + end_object, ///< the character for object end `}` + name_separator, ///< the name separator `:` + value_separator, ///< the value separator `,` + parse_error, ///< indicating a parse error + end_of_input ///< indicating the end of the input buffer + }; /// return name of values of type token_type (only used for errors) - static std::string token_type_name(const token_type t) + static const char* token_type_name(const token_type t) noexcept { switch (t) { @@ -7722,7 +11023,9 @@ class basic_json return "null literal"; case token_type::value_string: return "string literal"; - case token_type::value_number: + case lexer::token_type::value_unsigned: + case lexer::token_type::value_integer: + case lexer::token_type::value_float: return "number literal"; case token_type::begin_array: return "'['"; @@ -7748,1414 +11051,1460 @@ class basic_json } } - /*! - This function implements a scanner for JSON. It is specified using - regular expressions that try to follow RFC 7159 as close as possible. - These regular expressions are then translated into a minimized - deterministic finite automaton (DFA) by the tool - [re2c](http://re2c.org). As a result, the translated code for this - function consists of a large block of code with `goto` jumps. + explicit lexer(input_adapter_t adapter) + : ia(adapter), decimal_point_char(get_decimal_point()) + {} + + private: + ///////////////////// + // locales + ///////////////////// - @return the class of the next token read from the buffer + /// return the locale-dependent decimal point + static char get_decimal_point() noexcept + { + const auto loc = localeconv(); + assert(loc != nullptr); + return (loc->decimal_point == nullptr) ? '.' : loc->decimal_point[0]; + } - @complexity Linear in the length of the input.\n + ///////////////////// + // scan functions + ///////////////////// - Proposition: The loop below will always terminate for finite input.\n + /*! + @brief get codepoint from 4 hex characters following `\u` - Proof (by contradiction): Assume a finite input. To loop forever, the - loop must never hit code with a `break` statement. The only code - snippets without a `break` statement are the continue statements for - whitespace and byte-order-marks. To loop forever, the input must be an - infinite sequence of whitespace or byte-order-marks. This contradicts - the assumption of finite input, q.e.d. + @return codepoint or -1 in case of an error (e.g. EOF or non-hex + character) */ - token_type scan() + int get_codepoint() { - while (true) + // this function only makes sense after reading `\u` + assert(current == 'u'); + int codepoint = 0; + + // byte 1: \uXxxx + switch (get()) { - // pointer for backtracking information - m_marker = nullptr; - - // remember the begin of the token - m_start = m_cursor; - assert(m_start != nullptr); - - - { - lexer_char_t yych; - unsigned int yyaccept = 0; - static const unsigned char yybm[] = - { - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 32, 32, 0, 0, 32, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 160, 128, 0, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 192, 192, 192, 192, 192, 192, 192, 192, - 192, 192, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 0, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, - }; - if ((m_limit - m_cursor) < 5) - { - fill_line_buffer(5); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yybm[0 + yych] & 32) - { - goto basic_json_parser_6; - } - if (yych <= '[') - { - if (yych <= '-') - { - if (yych <= '"') - { - if (yych <= 0x00) - { - goto basic_json_parser_2; - } - if (yych <= '!') - { - goto basic_json_parser_4; - } - goto basic_json_parser_9; - } - else - { - if (yych <= '+') - { - goto basic_json_parser_4; - } - if (yych <= ',') - { - goto basic_json_parser_10; - } - goto basic_json_parser_12; - } - } - else - { - if (yych <= '9') - { - if (yych <= '/') - { - goto basic_json_parser_4; - } - if (yych <= '0') - { - goto basic_json_parser_13; - } - goto basic_json_parser_15; - } - else - { - if (yych <= ':') - { - goto basic_json_parser_17; - } - if (yych <= 'Z') - { - goto basic_json_parser_4; - } - goto basic_json_parser_19; - } - } - } - else - { - if (yych <= 'n') - { - if (yych <= 'e') - { - if (yych == ']') - { - goto basic_json_parser_21; - } - goto basic_json_parser_4; - } - else - { - if (yych <= 'f') - { - goto basic_json_parser_23; - } - if (yych <= 'm') - { - goto basic_json_parser_4; - } - goto basic_json_parser_24; - } - } - else - { - if (yych <= 'z') - { - if (yych == 't') - { - goto basic_json_parser_25; - } - goto basic_json_parser_4; - } - else - { - if (yych <= '{') - { - goto basic_json_parser_26; - } - if (yych == '}') - { - goto basic_json_parser_28; - } - goto basic_json_parser_4; - } - } - } -basic_json_parser_2: - ++m_cursor; - { - last_token_type = token_type::end_of_input; - break; - } -basic_json_parser_4: - ++m_cursor; -basic_json_parser_5: - { - last_token_type = token_type::parse_error; - break; - } -basic_json_parser_6: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yybm[0 + yych] & 32) - { - goto basic_json_parser_6; - } - { - continue; - } -basic_json_parser_9: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych <= 0x1F) - { - goto basic_json_parser_5; - } - if (yych <= 0x7F) - { - goto basic_json_parser_31; - } - if (yych <= 0xC1) - { - goto basic_json_parser_5; - } - if (yych <= 0xF4) - { - goto basic_json_parser_31; - } - goto basic_json_parser_5; -basic_json_parser_10: - ++m_cursor; - { - last_token_type = token_type::value_separator; - break; - } -basic_json_parser_12: - yych = *++m_cursor; - if (yych <= '/') - { - goto basic_json_parser_5; - } - if (yych <= '0') - { - goto basic_json_parser_13; - } - if (yych <= '9') - { - goto basic_json_parser_15; - } - goto basic_json_parser_5; -basic_json_parser_13: - yyaccept = 1; - yych = *(m_marker = ++m_cursor); - if (yych <= 'D') - { - if (yych == '.') - { - goto basic_json_parser_43; - } - } - else - { - if (yych <= 'E') - { - goto basic_json_parser_44; - } - if (yych == 'e') - { - goto basic_json_parser_44; - } - } -basic_json_parser_14: - { - last_token_type = token_type::value_number; - break; - } -basic_json_parser_15: - yyaccept = 1; - m_marker = ++m_cursor; - if ((m_limit - m_cursor) < 3) - { - fill_line_buffer(3); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yybm[0 + yych] & 64) - { - goto basic_json_parser_15; - } - if (yych <= 'D') - { - if (yych == '.') - { - goto basic_json_parser_43; - } - goto basic_json_parser_14; - } - else - { - if (yych <= 'E') - { - goto basic_json_parser_44; - } - if (yych == 'e') - { - goto basic_json_parser_44; - } - goto basic_json_parser_14; - } -basic_json_parser_17: - ++m_cursor; - { - last_token_type = token_type::name_separator; - break; - } -basic_json_parser_19: - ++m_cursor; - { - last_token_type = token_type::begin_array; - break; - } -basic_json_parser_21: - ++m_cursor; - { - last_token_type = token_type::end_array; - break; - } -basic_json_parser_23: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych == 'a') - { - goto basic_json_parser_45; - } - goto basic_json_parser_5; -basic_json_parser_24: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych == 'u') - { - goto basic_json_parser_46; - } - goto basic_json_parser_5; -basic_json_parser_25: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych == 'r') - { - goto basic_json_parser_47; - } - goto basic_json_parser_5; -basic_json_parser_26: - ++m_cursor; - { - last_token_type = token_type::begin_object; - break; - } -basic_json_parser_28: - ++m_cursor; - { - last_token_type = token_type::end_object; - break; - } -basic_json_parser_30: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; -basic_json_parser_31: - if (yybm[0 + yych] & 128) - { - goto basic_json_parser_30; - } - if (yych <= 0xE0) - { - if (yych <= '\\') - { - if (yych <= 0x1F) - { - goto basic_json_parser_32; - } - if (yych <= '"') - { - goto basic_json_parser_33; - } - goto basic_json_parser_35; - } - else - { - if (yych <= 0xC1) - { - goto basic_json_parser_32; - } - if (yych <= 0xDF) - { - goto basic_json_parser_36; - } - goto basic_json_parser_37; - } - } - else - { - if (yych <= 0xEF) - { - if (yych == 0xED) - { - goto basic_json_parser_39; - } - goto basic_json_parser_38; - } - else - { - if (yych <= 0xF0) - { - goto basic_json_parser_40; - } - if (yych <= 0xF3) - { - goto basic_json_parser_41; - } - if (yych <= 0xF4) - { - goto basic_json_parser_42; - } - } - } -basic_json_parser_32: - m_cursor = m_marker; - if (yyaccept == 0) - { - goto basic_json_parser_5; - } - else - { - goto basic_json_parser_14; - } -basic_json_parser_33: - ++m_cursor; + case '0': + break; + case '1': + codepoint += 0x1000; + break; + case '2': + codepoint += 0x2000; + break; + case '3': + codepoint += 0x3000; + break; + case '4': + codepoint += 0x4000; + break; + case '5': + codepoint += 0x5000; + break; + case '6': + codepoint += 0x6000; + break; + case '7': + codepoint += 0x7000; + break; + case '8': + codepoint += 0x8000; + break; + case '9': + codepoint += 0x9000; + break; + case 'A': + case 'a': + codepoint += 0xa000; + break; + case 'B': + case 'b': + codepoint += 0xb000; + break; + case 'C': + case 'c': + codepoint += 0xc000; + break; + case 'D': + case 'd': + codepoint += 0xd000; + break; + case 'E': + case 'e': + codepoint += 0xe000; + break; + case 'F': + case 'f': + codepoint += 0xf000; + break; + default: + return -1; + } + + // byte 2: \uxXxx + switch (get()) + { + case '0': + break; + case '1': + codepoint += 0x0100; + break; + case '2': + codepoint += 0x0200; + break; + case '3': + codepoint += 0x0300; + break; + case '4': + codepoint += 0x0400; + break; + case '5': + codepoint += 0x0500; + break; + case '6': + codepoint += 0x0600; + break; + case '7': + codepoint += 0x0700; + break; + case '8': + codepoint += 0x0800; + break; + case '9': + codepoint += 0x0900; + break; + case 'A': + case 'a': + codepoint += 0x0a00; + break; + case 'B': + case 'b': + codepoint += 0x0b00; + break; + case 'C': + case 'c': + codepoint += 0x0c00; + break; + case 'D': + case 'd': + codepoint += 0x0d00; + break; + case 'E': + case 'e': + codepoint += 0x0e00; + break; + case 'F': + case 'f': + codepoint += 0x0f00; + break; + default: + return -1; + } + + // byte 3: \uxxXx + switch (get()) + { + case '0': + break; + case '1': + codepoint += 0x0010; + break; + case '2': + codepoint += 0x0020; + break; + case '3': + codepoint += 0x0030; + break; + case '4': + codepoint += 0x0040; + break; + case '5': + codepoint += 0x0050; + break; + case '6': + codepoint += 0x0060; + break; + case '7': + codepoint += 0x0070; + break; + case '8': + codepoint += 0x0080; + break; + case '9': + codepoint += 0x0090; + break; + case 'A': + case 'a': + codepoint += 0x00a0; + break; + case 'B': + case 'b': + codepoint += 0x00b0; + break; + case 'C': + case 'c': + codepoint += 0x00c0; + break; + case 'D': + case 'd': + codepoint += 0x00d0; + break; + case 'E': + case 'e': + codepoint += 0x00e0; + break; + case 'F': + case 'f': + codepoint += 0x00f0; + break; + default: + return -1; + } + + // byte 4: \uxxxX + switch (get()) + { + case '0': + break; + case '1': + codepoint += 0x0001; + break; + case '2': + codepoint += 0x0002; + break; + case '3': + codepoint += 0x0003; + break; + case '4': + codepoint += 0x0004; + break; + case '5': + codepoint += 0x0005; + break; + case '6': + codepoint += 0x0006; + break; + case '7': + codepoint += 0x0007; + break; + case '8': + codepoint += 0x0008; + break; + case '9': + codepoint += 0x0009; + break; + case 'A': + case 'a': + codepoint += 0x000a; + break; + case 'B': + case 'b': + codepoint += 0x000b; + break; + case 'C': + case 'c': + codepoint += 0x000c; + break; + case 'D': + case 'd': + codepoint += 0x000d; + break; + case 'E': + case 'e': + codepoint += 0x000e; + break; + case 'F': + case 'f': + codepoint += 0x000f; + break; + default: + return -1; + } + + return codepoint; + } + + /*! + @brief create diagnostic representation of a codepoint + @return string "U+XXXX" for codepoint XXXX + */ + static std::string codepoint_to_string(int codepoint) + { + std::stringstream ss; + ss << "U+" << std::setw(4) << std::uppercase << std::setfill('0') << std::hex << codepoint; + return ss.str(); + } + + /*! + @brief scan a string literal + + This function scans a string according to Sect. 7 of RFC 7159. While + scanning, bytes are escaped and copied into buffer yytext. Then the + function returns successfully, yytext is null-terminated and yylen + contains the number of bytes in the string. + + @return token_type::value_string if string could be successfully + scanned, token_type::parse_error otherwise + + @note In case of errors, variable error_message contains a textual + description. + */ + token_type scan_string() + { + // reset yytext (ignore opening quote) + reset(); + + // we entered the function by reading an open quote + assert(current == '\"'); + + while (true) + { + // get next character + get(); + + switch (current) + { + // end of file while parsing string + case std::char_traits::eof(): { - last_token_type = token_type::value_string; - break; + error_message = "invalid string: missing closing quote"; + return token_type::parse_error; } -basic_json_parser_35: - ++m_cursor; - if (m_limit <= m_cursor) + + // closing quote + case '\"': { - fill_line_buffer(1); // LCOV_EXCL_LINE + // terminate yytext + add('\0'); + --yylen; + return token_type::value_string; } - yych = *m_cursor; - if (yych <= 'e') + + // escapes + case '\\': { - if (yych <= '/') - { - if (yych == '"') - { - goto basic_json_parser_30; - } - if (yych <= '.') - { - goto basic_json_parser_32; - } - goto basic_json_parser_30; - } - else + switch (get()) { - if (yych <= '\\') + // quotation mark + case '\"': + add('\"'); + break; + // reverse solidus + case '\\': + add('\\'); + break; + // solidus + case '/': + add('/'); + break; + // backspace + case 'b': + add('\b'); + break; + // form feed + case 'f': + add('\f'); + break; + // line feed + case 'n': + add('\n'); + break; + // carriage return + case 'r': + add('\r'); + break; + // tab + case 't': + add('\t'); + break; + + // unicode escapes + case 'u': { - if (yych <= '[') + int codepoint; + int codepoint1 = get_codepoint(); + + if (JSON_UNLIKELY(codepoint1 == -1)) { - goto basic_json_parser_32; + error_message = "invalid string: '\\u' must be followed by 4 hex digits"; + return token_type::parse_error; } - goto basic_json_parser_30; - } - else - { - if (yych == 'b') + + // check if code point is a high surrogate + if (0xD800 <= codepoint1 and codepoint1 <= 0xDBFF) { - goto basic_json_parser_30; + // expect next \uxxxx entry + if (JSON_LIKELY(get() == '\\' and get() == 'u')) + { + const int codepoint2 = get_codepoint(); + + if (JSON_UNLIKELY(codepoint2 == -1)) + { + error_message = "invalid string: '\\u' must be followed by 4 hex digits"; + return token_type::parse_error; + } + + // check if codepoint2 is a low surrogate + if (JSON_LIKELY(0xDC00 <= codepoint2 and codepoint2 <= 0xDFFF)) + { + codepoint = + // high surrogate occupies the most significant 22 bits + (codepoint1 << 10) + // low surrogate occupies the least significant 15 bits + + codepoint2 + // there is still the 0xD800, 0xDC00 and 0x10000 noise + // in the result so we have to subtract with: + // (0xD800 << 10) + DC00 - 0x10000 = 0x35FDC00 + - 0x35FDC00; + } + else + { + error_message = "invalid string: surrogate " + codepoint_to_string(codepoint1) + " must be followed by U+DC00..U+DFFF instead of " + codepoint_to_string(codepoint2); + return token_type::parse_error; + } + } + else + { + error_message = "invalid string: surrogate " + codepoint_to_string(codepoint1) + " must be followed by U+DC00..U+DFFF"; + return token_type::parse_error; + } } - goto basic_json_parser_32; - } - } - } - else - { - if (yych <= 'q') - { - if (yych <= 'f') - { - goto basic_json_parser_30; - } - if (yych == 'n') - { - goto basic_json_parser_30; - } - goto basic_json_parser_32; - } - else - { - if (yych <= 's') - { - if (yych <= 'r') + else { - goto basic_json_parser_30; + if (JSON_UNLIKELY(0xDC00 <= codepoint1 and codepoint1 <= 0xDFFF)) + { + error_message = "invalid string: surrogate " + codepoint_to_string(codepoint1) + " must follow U+D800..U+DBFF"; + return token_type::parse_error; + } + + // only work with first code point + codepoint = codepoint1; } - goto basic_json_parser_32; - } - else - { - if (yych <= 't') + + // result of the above calculation yields a proper codepoint + assert(0x00 <= codepoint and codepoint <= 0x10FFFF); + + // translate code point to bytes + if (codepoint < 0x80) + { + // 1-byte characters: 0xxxxxxx (ASCII) + add(codepoint); + } + else if (codepoint <= 0x7ff) + { + // 2-byte characters: 110xxxxx 10xxxxxx + add(0xC0 | (codepoint >> 6)); + add(0x80 | (codepoint & 0x3F)); + } + else if (codepoint <= 0xffff) { - goto basic_json_parser_30; + // 3-byte characters: 1110xxxx 10xxxxxx 10xxxxxx + add(0xE0 | (codepoint >> 12)); + add(0x80 | ((codepoint >> 6) & 0x3F)); + add(0x80 | (codepoint & 0x3F)); } - if (yych <= 'u') + else { - goto basic_json_parser_48; + // 4-byte characters: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx + add(0xF0 | (codepoint >> 18)); + add(0x80 | ((codepoint >> 12) & 0x3F)); + add(0x80 | ((codepoint >> 6) & 0x3F)); + add(0x80 | (codepoint & 0x3F)); } - goto basic_json_parser_32; + + break; } + + // other characters after escape + default: + error_message = "invalid string: forbidden character after backslash"; + return token_type::parse_error; } - } -basic_json_parser_36: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= 0x7F) - { - goto basic_json_parser_32; - } - if (yych <= 0xBF) - { - goto basic_json_parser_30; - } - goto basic_json_parser_32; -basic_json_parser_37: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= 0x9F) - { - goto basic_json_parser_32; - } - if (yych <= 0xBF) - { - goto basic_json_parser_36; - } - goto basic_json_parser_32; -basic_json_parser_38: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= 0x7F) - { - goto basic_json_parser_32; - } - if (yych <= 0xBF) - { - goto basic_json_parser_36; - } - goto basic_json_parser_32; -basic_json_parser_39: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= 0x7F) - { - goto basic_json_parser_32; - } - if (yych <= 0x9F) - { - goto basic_json_parser_36; - } - goto basic_json_parser_32; -basic_json_parser_40: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= 0x8F) - { - goto basic_json_parser_32; - } - if (yych <= 0xBF) - { - goto basic_json_parser_38; - } - goto basic_json_parser_32; -basic_json_parser_41: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= 0x7F) - { - goto basic_json_parser_32; - } - if (yych <= 0xBF) - { - goto basic_json_parser_38; - } - goto basic_json_parser_32; -basic_json_parser_42: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= 0x7F) - { - goto basic_json_parser_32; - } - if (yych <= 0x8F) - { - goto basic_json_parser_38; - } - goto basic_json_parser_32; -basic_json_parser_43: - yych = *++m_cursor; - if (yych <= '/') - { - goto basic_json_parser_32; - } - if (yych <= '9') - { - goto basic_json_parser_49; - } - goto basic_json_parser_32; -basic_json_parser_44: - yych = *++m_cursor; - if (yych <= ',') - { - if (yych == '+') - { - goto basic_json_parser_51; - } - goto basic_json_parser_32; - } - else - { - if (yych <= '-') - { - goto basic_json_parser_51; - } - if (yych <= '/') - { - goto basic_json_parser_32; - } - if (yych <= '9') - { - goto basic_json_parser_52; - } - goto basic_json_parser_32; - } -basic_json_parser_45: - yych = *++m_cursor; - if (yych == 'l') - { - goto basic_json_parser_54; - } - goto basic_json_parser_32; -basic_json_parser_46: - yych = *++m_cursor; - if (yych == 'l') - { - goto basic_json_parser_55; - } - goto basic_json_parser_32; -basic_json_parser_47: - yych = *++m_cursor; - if (yych == 'u') - { - goto basic_json_parser_56; - } - goto basic_json_parser_32; -basic_json_parser_48: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= '@') - { - if (yych <= '/') - { - goto basic_json_parser_32; - } - if (yych <= '9') - { - goto basic_json_parser_57; - } - goto basic_json_parser_32; - } - else - { - if (yych <= 'F') - { - goto basic_json_parser_57; - } - if (yych <= '`') - { - goto basic_json_parser_32; - } - if (yych <= 'f') - { - goto basic_json_parser_57; - } - goto basic_json_parser_32; - } -basic_json_parser_49: - yyaccept = 1; - m_marker = ++m_cursor; - if ((m_limit - m_cursor) < 3) - { - fill_line_buffer(3); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= 'D') - { - if (yych <= '/') - { - goto basic_json_parser_14; - } - if (yych <= '9') - { - goto basic_json_parser_49; - } - goto basic_json_parser_14; - } - else - { - if (yych <= 'E') - { - goto basic_json_parser_44; - } - if (yych == 'e') - { - goto basic_json_parser_44; - } - goto basic_json_parser_14; - } -basic_json_parser_51: - yych = *++m_cursor; - if (yych <= '/') - { - goto basic_json_parser_32; - } - if (yych >= ':') - { - goto basic_json_parser_32; - } -basic_json_parser_52: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= '/') - { - goto basic_json_parser_14; - } - if (yych <= '9') - { - goto basic_json_parser_52; - } - goto basic_json_parser_14; -basic_json_parser_54: - yych = *++m_cursor; - if (yych == 's') - { - goto basic_json_parser_58; - } - goto basic_json_parser_32; -basic_json_parser_55: - yych = *++m_cursor; - if (yych == 'l') - { - goto basic_json_parser_59; - } - goto basic_json_parser_32; -basic_json_parser_56: - yych = *++m_cursor; - if (yych == 'e') - { - goto basic_json_parser_61; - } - goto basic_json_parser_32; -basic_json_parser_57: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= '@') - { - if (yych <= '/') - { - goto basic_json_parser_32; - } - if (yych <= '9') - { - goto basic_json_parser_63; - } - goto basic_json_parser_32; - } - else - { - if (yych <= 'F') - { - goto basic_json_parser_63; - } - if (yych <= '`') - { - goto basic_json_parser_32; - } - if (yych <= 'f') - { - goto basic_json_parser_63; - } - goto basic_json_parser_32; - } -basic_json_parser_58: - yych = *++m_cursor; - if (yych == 'e') - { - goto basic_json_parser_64; - } - goto basic_json_parser_32; -basic_json_parser_59: - ++m_cursor; - { - last_token_type = token_type::literal_null; + break; } -basic_json_parser_61: - ++m_cursor; - { - last_token_type = token_type::literal_true; + + // invalid control characters + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x08: + case 0x09: + case 0x0a: + case 0x0b: + case 0x0c: + case 0x0d: + case 0x0e: + case 0x0f: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + case 0x18: + case 0x19: + case 0x1a: + case 0x1b: + case 0x1c: + case 0x1d: + case 0x1e: + case 0x1f: + { + error_message = "invalid string: control character " + codepoint_to_string(current) + " must be escaped"; + return token_type::parse_error; + } + + // U+0020..U+007F (except U+0022 (quote) and U+005C (backspace)) + case 0x20: + case 0x21: + case 0x23: + case 0x24: + case 0x25: + case 0x26: + case 0x27: + case 0x28: + case 0x29: + case 0x2a: + case 0x2b: + case 0x2c: + case 0x2d: + case 0x2e: + case 0x2f: + case 0x30: + case 0x31: + case 0x32: + case 0x33: + case 0x34: + case 0x35: + case 0x36: + case 0x37: + case 0x38: + case 0x39: + case 0x3a: + case 0x3b: + case 0x3c: + case 0x3d: + case 0x3e: + case 0x3f: + case 0x40: + case 0x41: + case 0x42: + case 0x43: + case 0x44: + case 0x45: + case 0x46: + case 0x47: + case 0x48: + case 0x49: + case 0x4a: + case 0x4b: + case 0x4c: + case 0x4d: + case 0x4e: + case 0x4f: + case 0x50: + case 0x51: + case 0x52: + case 0x53: + case 0x54: + case 0x55: + case 0x56: + case 0x57: + case 0x58: + case 0x59: + case 0x5a: + case 0x5b: + case 0x5d: + case 0x5e: + case 0x5f: + case 0x60: + case 0x61: + case 0x62: + case 0x63: + case 0x64: + case 0x65: + case 0x66: + case 0x67: + case 0x68: + case 0x69: + case 0x6a: + case 0x6b: + case 0x6c: + case 0x6d: + case 0x6e: + case 0x6f: + case 0x70: + case 0x71: + case 0x72: + case 0x73: + case 0x74: + case 0x75: + case 0x76: + case 0x77: + case 0x78: + case 0x79: + case 0x7a: + case 0x7b: + case 0x7c: + case 0x7d: + case 0x7e: + case 0x7f: + { + add(current); break; } -basic_json_parser_63: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE - } - yych = *m_cursor; - if (yych <= '@') - { - if (yych <= '/') - { - goto basic_json_parser_32; - } - if (yych <= '9') + + // U+0080..U+07FF: bytes C2..DF 80..BF + case 0xc2: + case 0xc3: + case 0xc4: + case 0xc5: + case 0xc6: + case 0xc7: + case 0xc8: + case 0xc9: + case 0xca: + case 0xcb: + case 0xcc: + case 0xcd: + case 0xce: + case 0xcf: + case 0xd0: + case 0xd1: + case 0xd2: + case 0xd3: + case 0xd4: + case 0xd5: + case 0xd6: + case 0xd7: + case 0xd8: + case 0xd9: + case 0xda: + case 0xdb: + case 0xdc: + case 0xdd: + case 0xde: + case 0xdf: + { + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) { - goto basic_json_parser_66; + add(current); + continue; } - goto basic_json_parser_32; + + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; } - else + + // U+0800..U+0FFF: bytes E0 A0..BF 80..BF + case 0xe0: { - if (yych <= 'F') + add(current); + get(); + if (JSON_LIKELY(0xa0 <= current and current <= 0xbf)) { - goto basic_json_parser_66; - } - if (yych <= '`') - { - goto basic_json_parser_32; + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + continue; + } } - if (yych <= 'f') + + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; + } + + // U+1000..U+CFFF: bytes E1..EC 80..BF 80..BF + // U+E000..U+FFFF: bytes EE..EF 80..BF 80..BF + case 0xe1: + case 0xe2: + case 0xe3: + case 0xe4: + case 0xe5: + case 0xe6: + case 0xe7: + case 0xe8: + case 0xe9: + case 0xea: + case 0xeb: + case 0xec: + case 0xee: + case 0xef: + { + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) { - goto basic_json_parser_66; + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + continue; + } } - goto basic_json_parser_32; - } -basic_json_parser_64: - ++m_cursor; - { - last_token_type = token_type::literal_false; - break; - } -basic_json_parser_66: - ++m_cursor; - if (m_limit <= m_cursor) - { - fill_line_buffer(1); // LCOV_EXCL_LINE + + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; } - yych = *m_cursor; - if (yych <= '@') + + // U+D000..U+D7FF: bytes ED 80..9F 80..BF + case 0xed: { - if (yych <= '/') + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0x9f)) { - goto basic_json_parser_32; + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + continue; + } } - if (yych <= '9') + + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; + } + + // U+10000..U+3FFFF F0 90..BF 80..BF 80..BF + case 0xf0: + { + add(current); + get(); + if (JSON_LIKELY(0x90 <= current and current <= 0xbf)) { - goto basic_json_parser_30; + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + continue; + } + } } - goto basic_json_parser_32; + + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; } - else + + // U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF + case 0xf1: + case 0xf2: + case 0xf3: { - if (yych <= 'F') - { - goto basic_json_parser_30; - } - if (yych <= '`') + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) { - goto basic_json_parser_32; + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + continue; + } + } } - if (yych <= 'f') + + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; + } + + // U+100000..U+10FFFF F4 80..8F 80..BF 80..BF + case 0xf4: + { + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0x8f)) { - goto basic_json_parser_30; + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + get(); + if (JSON_LIKELY(0x80 <= current and current <= 0xbf)) + { + add(current); + continue; + } + } } - goto basic_json_parser_32; + + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; } - } + // remaining bytes (80..C1 and F5..FF) are ill-formed + default: + { + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; + } + } } + } + + static void strtof(float& f, const char* str, char** endptr) noexcept + { + f = std::strtof(str, endptr); + } + + static void strtof(double& f, const char* str, char** endptr) noexcept + { + f = std::strtod(str, endptr); + } - return last_token_type; + static void strtof(long double& f, const char* str, char** endptr) noexcept + { + f = std::strtold(str, endptr); } /*! - @brief append data from the stream to the line buffer - - This function is called by the scan() function when the end of the - buffer (`m_limit`) is reached and the `m_cursor` pointer cannot be - incremented without leaving the limits of the line buffer. Note re2c - decides when to call this function. - - If the lexer reads from contiguous storage, there is no trailing null - byte. Therefore, this function must make sure to add these padding - null bytes. - - If the lexer reads from an input stream, this function reads the next - line of the input. - - @pre - p p p p p p u u u u u x . . . . . . - ^ ^ ^ ^ - m_content m_start | m_limit - m_cursor - - @post - u u u u u x x x x x x x . . . . . . - ^ ^ ^ - | m_cursor m_limit - m_start - m_content + @brief scan a number literal + + This function scans a string according to Sect. 6 of RFC 7159. + + The function is realized with a deterministic finite state machine + derived from the grammar described in RFC 7159. Starting in state + "init", the input is read and used to determined the next state. Only + state "done" accepts the number. State "error" is a trap state to model + errors. In the table below, "anything" means any character but the ones + listed before. + + state | 0 | 1-9 | e E | + | - | . | anything + ---------|----------|----------|----------|---------|---------|----------|----------- + init | zero | any1 | [error] | [error] | minus | [error] | [error] + minus | zero | any1 | [error] | [error] | [error] | [error] | [error] + zero | done | done | exponent | done | done | decimal1 | done + any1 | any1 | any1 | exponent | done | done | decimal1 | done + decimal1 | decimal2 | [error] | [error] | [error] | [error] | [error] | [error] + decimal2 | decimal2 | decimal2 | exponent | done | done | done | done + exponent | any2 | any2 | [error] | sign | sign | [error] | [error] + sign | any2 | any2 | [error] | [error] | [error] | [error] | [error] + any2 | any2 | any2 | done | done | done | done | done + + The state machine is realized with one label per state (prefixed with + "scan_number_") and `goto` statements between them. The state machine + contains cycles, but any cycle can be left when EOF is read. Therefore, + the function is guaranteed to terminate. + + During scanning, the read bytes are stored in yytext. This string is + then converted to a signed integer, an unsigned integer, or a + floating-point number. + + @return token_type::value_unsigned, token_type::value_integer, or + token_type::value_float if number could be successfully scanned, + token_type::parse_error otherwise + + @note The scanner is independent of the current locale. Internally, the + locale's decimal point is used instead of `.` to work with the + locale-dependent converters. */ - void fill_line_buffer(size_t n = 0) + token_type scan_number() { - // if line buffer is used, m_content points to its data - assert(m_line_buffer.empty() - or m_content == reinterpret_cast(m_line_buffer.data())); + // reset yytext to store the number's bytes + reset(); + + // the type of the parsed number; initially set to unsigned; will be + // changed if minus sign, decimal point or exponent is read + token_type number_type = token_type::value_unsigned; + + // state (init): we just found out we need to scan a number + switch (current) + { + case '-': + { + add(current); + goto scan_number_minus; + } - // if line buffer is used, m_limit is set past the end of its data - assert(m_line_buffer.empty() - or m_limit == m_content + m_line_buffer.size()); + case '0': + { + add(current); + goto scan_number_zero; + } - // pointer relationships - assert(m_content <= m_start); - assert(m_start <= m_cursor); - assert(m_cursor <= m_limit); - assert(m_marker == nullptr or m_marker <= m_limit); + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any1; + } - // number of processed characters (p) - const size_t num_processed_chars = static_cast(m_start - m_content); - // offset for m_marker wrt. to m_start - const auto offset_marker = (m_marker == nullptr) ? 0 : m_marker - m_start; - // number of unprocessed characters (u) - const auto offset_cursor = m_cursor - m_start; + default: + { + // all other characters are rejected outside scan_number() + assert(false); // LCOV_EXCL_LINE + } + } - // no stream is used or end of file is reached - if (m_stream == nullptr or m_stream->eof()) +scan_number_minus: + // state: we just parsed a leading minus sign + number_type = token_type::value_integer; + switch (get()) { - // m_start may or may not be pointing into m_line_buffer at - // this point. We trust the standand library to do the right - // thing. See http://stackoverflow.com/q/28142011/266378 - m_line_buffer.assign(m_start, m_limit); + case '0': + { + add(current); + goto scan_number_zero; + } + + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any1; + } - // append n characters to make sure that there is sufficient - // space between m_cursor and m_limit - m_line_buffer.append(1, '\x00'); - if (n > 0) + default: { - m_line_buffer.append(n - 1, '\x01'); + error_message = "invalid number; expected digit after '-'"; + return token_type::parse_error; } } - else + +scan_number_zero: + // state: we just parse a zero (maybe with a leading minus sign) + switch (get()) { - // delete processed characters from line buffer - m_line_buffer.erase(0, num_processed_chars); - // read next line from input stream - m_line_buffer_tmp.clear(); - std::getline(*m_stream, m_line_buffer_tmp, '\n'); + case '.': + { + add(decimal_point_char); + goto scan_number_decimal1; + } + + case 'e': + case 'E': + { + add(current); + goto scan_number_exponent; + } - // add line with newline symbol to the line buffer - m_line_buffer += m_line_buffer_tmp; - m_line_buffer.push_back('\n'); + default: + { + goto scan_number_done; + } } - // set pointers - m_content = reinterpret_cast(m_line_buffer.data()); - assert(m_content != nullptr); - m_start = m_content; - m_marker = m_start + offset_marker; - m_cursor = m_start + offset_cursor; - m_limit = m_start + m_line_buffer.size(); - } +scan_number_any1: + // state: we just parsed a number 0-9 (maybe with a leading minus sign) + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any1; + } - /// return string representation of last read token - string_t get_token_string() const - { - assert(m_start != nullptr); - return string_t(reinterpret_cast(m_start), - static_cast(m_cursor - m_start)); - } + case '.': + { + add(decimal_point_char); + goto scan_number_decimal1; + } - /*! - @brief return string value for string tokens - - The function iterates the characters between the opening and closing - quotes of the string value. The complete string is the range - [m_start,m_cursor). Consequently, we iterate from m_start+1 to - m_cursor-1. - - We differentiate two cases: - - 1. Escaped characters. In this case, a new character is constructed - according to the nature of the escape. Some escapes create new - characters (e.g., `"\\n"` is replaced by `"\n"`), some are copied - as is (e.g., `"\\\\"`). Furthermore, Unicode escapes of the shape - `"\\uxxxx"` need special care. In this case, to_unicode takes care - of the construction of the values. - 2. Unescaped characters are copied as is. - - @pre `m_cursor - m_start >= 2`, meaning the length of the last token - is at least 2 bytes which is trivially true for any string (which - consists of at least two quotes). - - " c1 c2 c3 ... " - ^ ^ - m_start m_cursor - - @complexity Linear in the length of the string.\n - - Lemma: The loop body will always terminate.\n - - Proof (by contradiction): Assume the loop body does not terminate. As - the loop body does not contain another loop, one of the called - functions must never return. The called functions are `std::strtoul` - and to_unicode. Neither function can loop forever, so the loop body - will never loop forever which contradicts the assumption that the loop - body does not terminate, q.e.d.\n - - Lemma: The loop condition for the for loop is eventually false.\n - - Proof (by contradiction): Assume the loop does not terminate. Due to - the above lemma, this can only be due to a tautological loop - condition; that is, the loop condition i < m_cursor - 1 must always be - true. Let x be the change of i for any loop iteration. Then - m_start + 1 + x < m_cursor - 1 must hold to loop indefinitely. This - can be rephrased to m_cursor - m_start - 2 > x. With the - precondition, we x <= 0, meaning that the loop condition holds - indefinitly if i is always decreased. However, observe that the value - of i is strictly increasing with each iteration, as it is incremented - by 1 in the iteration expression and never decremented inside the loop - body. Hence, the loop condition will eventually be false which - contradicts the assumption that the loop condition is a tautology, - q.e.d. - - @return string value of current token without opening and closing - quotes - @throw std::out_of_range if to_unicode fails - */ - string_t get_string() const - { - assert(m_cursor - m_start >= 2); + case 'e': + case 'E': + { + add(current); + goto scan_number_exponent; + } - string_t result; - result.reserve(static_cast(m_cursor - m_start - 2)); + default: + { + goto scan_number_done; + } + } - // iterate the result between the quotes - for (const lexer_char_t* i = m_start + 1; i < m_cursor - 1; ++i) +scan_number_decimal1: + // state: we just parsed a decimal point + number_type = token_type::value_float; + switch (get()) { - // find next escape character - auto e = std::find(i, m_cursor - 1, '\\'); - if (e != i) + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': { - // see https://github.com/nlohmann/json/issues/365#issuecomment-262874705 - for (auto k = i; k < e; k++) - { - result.push_back(static_cast(*k)); - } - i = e - 1; // -1 because of ++i + add(current); + goto scan_number_decimal2; } - else + + default: { - // processing escaped character - // read next character - ++i; + error_message = "invalid number; expected digit after '.'"; + return token_type::parse_error; + } + } - switch (*i) - { - // the default escapes - case 't': - { - result += "\t"; - break; - } - case 'b': - { - result += "\b"; - break; - } - case 'f': - { - result += "\f"; - break; - } - case 'n': - { - result += "\n"; - break; - } - case 'r': - { - result += "\r"; - break; - } - case '\\': - { - result += "\\"; - break; - } - case '/': - { - result += "/"; - break; - } - case '"': - { - result += "\""; - break; - } +scan_number_decimal2: + // we just parsed at least one number after a decimal point + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_decimal2; + } - // unicode - case 'u': - { - // get code xxxx from uxxxx - auto codepoint = std::strtoul(std::string(reinterpret_cast(i + 1), - 4).c_str(), nullptr, 16); + case 'e': + case 'E': + { + add(current); + goto scan_number_exponent; + } - // check if codepoint is a high surrogate - if (codepoint >= 0xD800 and codepoint <= 0xDBFF) - { - // make sure there is a subsequent unicode - if ((i + 6 >= m_limit) or * (i + 5) != '\\' or * (i + 6) != 'u') - { - throw std::invalid_argument("missing low surrogate"); - } + default: + { + goto scan_number_done; + } + } - // get code yyyy from uxxxx\uyyyy - auto codepoint2 = std::strtoul(std::string(reinterpret_cast - (i + 7), 4).c_str(), nullptr, 16); - result += to_unicode(codepoint, codepoint2); - // skip the next 10 characters (xxxx\uyyyy) - i += 10; - } - else if (codepoint >= 0xDC00 and codepoint <= 0xDFFF) - { - // we found a lone low surrogate - throw std::invalid_argument("missing high surrogate"); - } - else - { - // add unicode character(s) - result += to_unicode(codepoint); - // skip the next four characters (xxxx) - i += 4; - } - break; - } - } +scan_number_exponent: + // we just parsed an exponent + number_type = token_type::value_float; + switch (get()) + { + case '+': + case '-': + { + add(current); + goto scan_number_sign; + } + + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any2; + } + + default: + { + error_message = "invalid number; expected '+', '-', or digit after exponent"; + return token_type::parse_error; } } - return result; - } +scan_number_sign: + // we just parsed an exponent sign + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any2; + } - /*! - @brief parse floating point number + default: + { + error_message = "invalid number; expected digit after exponent sign"; + return token_type::parse_error; + } + } + +scan_number_any2: + // we just parsed a number after the exponent or exponent sign + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any2; + } + + default: + { + goto scan_number_done; + } + } - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). +scan_number_done: + // unget the character after the number (we only read it to know + // that we are done scanning a number) + --chars_read; + next_unget = true; - @param[in] type the @ref number_float_t in use + // terminate token + add('\0'); + --yylen; - @param[in,out] endptr recieves a pointer to the first character after - the number + // try to parse integers first and fall back to floats + if (number_type == token_type::value_unsigned) + { + char* endptr = nullptr; + errno = 0; + const auto x = std::strtoull(yytext.data(), &endptr, 10); - @return the floating point number - */ - long double str_to_float_t(long double* /* type */, char** endptr) const - { - return std::strtold(reinterpret_cast(m_start), endptr); - } + // we checked the number format before + assert(endptr == yytext.data() + yylen); - /*! - @brief parse floating point number + if (errno == 0) + { + value_unsigned = static_cast(x); + if (value_unsigned == x) + { + return token_type::value_unsigned; + } + } + } + else if (number_type == token_type::value_integer) + { + char* endptr = nullptr; + errno = 0; + const auto x = std::strtoll(yytext.data(), &endptr, 10); - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). + // we checked the number format before + assert(endptr == yytext.data() + yylen); - @param[in] type the @ref number_float_t in use + if (errno == 0) + { + value_integer = static_cast(x); + if (value_integer == x) + { + return token_type::value_integer; + } + } + } - @param[in,out] endptr recieves a pointer to the first character after - the number + // this code is reached if we parse a floating-point number or if + // an integer conversion above failed + strtof(value_float, yytext.data(), nullptr); + return token_type::value_float; + } - @return the floating point number - */ - double str_to_float_t(double* /* type */, char** endptr) const + token_type scan_true() { - return std::strtod(reinterpret_cast(m_start), endptr); + assert(current == 't'); + if (JSON_LIKELY((get() == 'r' and get() == 'u' and get() == 'e'))) + { + return token_type::literal_true; + } + + error_message = "invalid literal; expected 'true'"; + return token_type::parse_error; } - /*! - @brief parse floating point number + token_type scan_false() + { + assert(current == 'f'); + if (JSON_LIKELY((get() == 'a' and get() == 'l' and get() == 's' and get() == 'e'))) + { + return token_type::literal_false; + } + + error_message = "invalid literal; expected 'false'"; + return token_type::parse_error; + } - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). + token_type scan_null() + { + assert(current == 'n'); + if (JSON_LIKELY((get() == 'u' and get() == 'l' and get() == 'l'))) + { + return token_type::literal_null; + } - @param[in] type the @ref number_float_t in use + error_message = "invalid literal; expected 'null'"; + return token_type::parse_error; + } - @param[in,out] endptr recieves a pointer to the first character after - the number + ///////////////////// + // input management + ///////////////////// - @return the floating point number - */ - float str_to_float_t(float* /* type */, char** endptr) const + /// reset yytext + void reset() noexcept { - return std::strtof(reinterpret_cast(m_start), endptr); + yylen = 0; + start_pos = chars_read - 1; } - /*! - @brief return number value for number tokens + /// get a character from the input + int get() + { + ++chars_read; + return next_unget + ? (next_unget = false, current) + : (current = ia->get_character()); + } - This function translates the last token into the most appropriate - number type (either integer, unsigned integer or floating point), - which is passed back to the caller via the result parameter. + /// add a character to yytext + void add(int c) + { + // resize yytext if necessary; this condition is deemed unlikely, + // because we start with a 1024-byte buffer + if (JSON_UNLIKELY((yylen + 1 > yytext.capacity()))) + { + yytext.resize(2 * yytext.capacity(), '\0'); + } + yytext[yylen++] = static_cast(c); + } - This function parses the integer component up to the radix point or - exponent while collecting information about the 'floating point - representation', which it stores in the result parameter. If there is - no radix point or exponent, and the number can fit into a @ref - number_integer_t or @ref number_unsigned_t then it sets the result - parameter accordingly. + public: + ///////////////////// + // value getters + ///////////////////// - If the number is a floating point number the number is then parsed - using @a std:strtod (or @a std:strtof or @a std::strtold). + /// return integer value + constexpr number_integer_t get_number_integer() const noexcept + { + return value_integer; + } - @param[out] result @ref basic_json object to receive the number, or - NAN if the conversion read past the current token. The latter case - needs to be treated by the caller function. - */ - void get_number(basic_json& result) const + /// return unsigned integer value + constexpr number_unsigned_t get_number_unsigned() const noexcept { - assert(m_start != nullptr); + return value_unsigned; + } - const lexer::lexer_char_t* curptr = m_start; + /// return floating-point value + constexpr number_float_t get_number_float() const noexcept + { + return value_float; + } - // accumulate the integer conversion result (unsigned for now) - number_unsigned_t value = 0; + /// return string value + const std::string get_string() + { + // yytext cannot be returned as char*, because it may contain a + // null byte (parsed as "\u0000") + return std::string(yytext.data(), yylen); + } - // maximum absolute value of the relevant integer type - number_unsigned_t max; + ///////////////////// + // diagnostics + ///////////////////// - // temporarily store the type to avoid unecessary bitfield access - value_t type; + /// return position of last read token + constexpr size_t get_position() const noexcept + { + return chars_read; + } - // look for sign - if (*curptr == '-') - { - type = value_t::number_integer; - max = static_cast((std::numeric_limits::max)()) + 1; - curptr++; - } - else - { - type = value_t::number_unsigned; - max = static_cast((std::numeric_limits::max)()); - } + /// return the last read token (for errors only) + std::string get_token_string() const + { + // get the raw byte sequence of the last token + std::string s = ia->read(start_pos, chars_read - start_pos); - // count the significant figures - for (; curptr < m_cursor; curptr++) + // escape control characters + std::string result; + for (auto c : s) { - // quickly skip tests if a digit - if (*curptr < '0' || *curptr > '9') + if (c == '\0' or c == std::char_traits::eof()) { - if (*curptr == '.') - { - // don't count '.' but change to float - type = value_t::number_float; - continue; - } - // assume exponent (if not then will fail parse): change to - // float, stop counting and record exponent details - type = value_t::number_float; - break; + // ignore EOF + continue; } - - // skip if definitely not an integer - if (type != value_t::number_float) + else if ('\x00' <= c and c <= '\x1f') { - // multiply last value by ten and add the new digit - auto temp = value * 10 + *curptr - '0'; - - // test for overflow - if (temp < value || temp > max) - { - // overflow - type = value_t::number_float; - } - else - { - // no overflow - save it - value = temp; - } + // escape control characters + result += "<" + codepoint_to_string(c) + ">"; } - } - - // save the value (if not a float) - if (type == value_t::number_unsigned) - { - result.m_value.number_unsigned = value; - } - else if (type == value_t::number_integer) - { - result.m_value.number_integer = -static_cast(value); - } - else - { - // parse with strtod - result.m_value.number_float = str_to_float_t(static_cast(nullptr), NULL); - - // replace infinity and NAN by null - if (not std::isfinite(result.m_value.number_float)) + else { - type = value_t::null; - result.m_value = basic_json::json_value(); + // add character as is + result.append(1, c); } } - // save the type - result.m_type = type; + return result; + } + + /// return syntax error message + const std::string& get_error_message() const noexcept + { + return error_message; + } + + ///////////////////// + // actual scanner + ///////////////////// + + token_type scan() + { + // read next character and ignore whitespace + do + { + get(); + } + while (current == ' ' or current == '\t' or current == '\n' or current == '\r'); + + switch (current) + { + // structural characters + case '[': + return token_type::begin_array; + case ']': + return token_type::end_array; + case '{': + return token_type::begin_object; + case '}': + return token_type::end_object; + case ':': + return token_type::name_separator; + case ',': + return token_type::value_separator; + + // literals + case 't': + return scan_true(); + case 'f': + return scan_false(); + case 'n': + return scan_null(); + + // string + case '\"': + return scan_string(); + + // number + case '-': + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + return scan_number(); + + // end of input (the null byte is needed when parsing from + // string literals) + case '\0': + case std::char_traits::eof(): + return token_type::end_of_input; + + // error + default: + error_message = "invalid literal"; + return token_type::parse_error; + } } private: - /// optional input stream - std::istream* m_stream = nullptr; - /// line buffer buffer for m_stream - string_t m_line_buffer {}; - /// used for filling m_line_buffer - string_t m_line_buffer_tmp {}; - /// the buffer pointer - const lexer_char_t* m_content = nullptr; - /// pointer to the beginning of the current symbol - const lexer_char_t* m_start = nullptr; - /// pointer for backtracking information - const lexer_char_t* m_marker = nullptr; - /// pointer to the current symbol - const lexer_char_t* m_cursor = nullptr; - /// pointer to the end of the buffer - const lexer_char_t* m_limit = nullptr; - /// the last token type - token_type last_token_type = token_type::end_of_input; + /// input adapter + input_adapter_t ia = nullptr; + + /// the current character + int current = std::char_traits::eof(); + + /// whether get() should return the last character again + bool next_unget = false; + + /// the number of characters read + size_t chars_read = 0; + /// the start position of the current token + size_t start_pos = 0; + + /// buffer for variable-length tokens (numbers, strings) + std::vector yytext = std::vector(1024, '\0'); + /// current index in yytext + size_t yylen = 0; + + /// a description of occurred lexer errors + std::string error_message = ""; + + // number values + number_integer_t value_integer = 0; + number_unsigned_t value_unsigned = 0; + number_float_t value_float = 0; + + /// the decimal point + const char decimal_point_char = '.'; }; /*! @@ -9166,30 +12515,23 @@ basic_json_parser_66: class parser { public: - /// a parser reading from a string literal - parser(const char* buff, const parser_callback_t cb = nullptr) - : callback(cb), - m_lexer(reinterpret_cast(buff), std::strlen(buff)) + /// a parser reading from an input adapter + explicit parser(input_adapter_t adapter, + const parser_callback_t cb = nullptr) + : callback(cb), m_lexer(adapter) {} - /// a parser reading from an input stream - parser(std::istream& is, const parser_callback_t cb = nullptr) - : callback(cb), m_lexer(is) - {} + /*! + @brief public parser interface - /// a parser reading from an iterator range with contiguous storage - template::iterator_category, std::random_access_iterator_tag>::value - , int>::type - = 0> - parser(IteratorType first, IteratorType last, const parser_callback_t cb = nullptr) - : callback(cb), - m_lexer(reinterpret_cast(&(*first)), - static_cast(std::distance(first, last))) - {} + @param[in] strict whether to expect the last token to be EOF + @return parsed JSON value - /// public parser interface - basic_json parse() + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + */ + basic_json parse(const bool strict = true) { // read first token get_token(); @@ -9197,15 +12539,48 @@ basic_json_parser_66: basic_json result = parse_internal(true); result.assert_invariant(); - expect(lexer::token_type::end_of_input); + if (strict) + { + get_token(); + expect(lexer::token_type::end_of_input); + } // return parser result and replace it with null in case the // top-level value was discarded by the callback function return result.is_discarded() ? basic_json() : std::move(result); } + /*! + @brief public accept interface + + @param[in] strict whether to expect the last token to be EOF + @return whether the input is a proper JSON text + */ + bool accept(const bool strict = true) + { + // read first token + get_token(); + + if (not accept_internal()) + { + return false; + } + + if (strict and get_token() != lexer::token_type::end_of_input) + { + return false; + } + + return true; + } + private: - /// the actual parser + /*! + @brief the actual parser + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + */ basic_json parse_internal(bool keep) { auto result = basic_json(value_t::discarded); @@ -9228,7 +12603,6 @@ basic_json_parser_66: // closing } -> we are done if (last_token == lexer::token_type::end_object) { - get_token(); if (keep and callback and not callback(--depth, parse_event_t::object_end, result)) { result = basic_json(value_t::discarded); @@ -9236,18 +12610,9 @@ basic_json_parser_66: return result; } - // no comma is expected here - unexpect(lexer::token_type::value_separator); - - // otherwise: parse key-value pairs - do + // parse values + while (true) { - // ugly, but could be fixed with loop reorganization - if (last_token == lexer::token_type::value_separator) - { - get_token(); - } - // store key expect(lexer::token_type::value_string); const auto key = m_lexer.get_string(); @@ -9277,12 +12642,20 @@ basic_json_parser_66: { result[key] = std::move(value); } + + // comma -> next value + get_token(); + if (last_token == lexer::token_type::value_separator) + { + get_token(); + continue; + } + + // closing } + expect(lexer::token_type::end_object); + break; } - while (last_token == lexer::token_type::value_separator); - // closing } - expect(lexer::token_type::end_object); - get_token(); if (keep and callback and not callback(--depth, parse_event_t::object_end, result)) { result = basic_json(value_t::discarded); @@ -9307,7 +12680,6 @@ basic_json_parser_66: // closing ] -> we are done if (last_token == lexer::token_type::end_array) { - get_token(); if (callback and not callback(--depth, parse_event_t::array_end, result)) { result = basic_json(value_t::discarded); @@ -9315,30 +12687,29 @@ basic_json_parser_66: return result; } - // no comma is expected here - unexpect(lexer::token_type::value_separator); - - // otherwise: parse values - do + // parse values + while (true) { - // ugly, but could be fixed with loop reorganization - if (last_token == lexer::token_type::value_separator) - { - get_token(); - } - // parse value auto value = parse_internal(keep); if (keep and not value.is_discarded()) { result.push_back(std::move(value)); } + + // comma -> next value + get_token(); + if (last_token == lexer::token_type::value_separator) + { + get_token(); + continue; + } + + // closing ] + expect(lexer::token_type::end_array); + break; } - while (last_token == lexer::token_type::value_separator); - // closing ] - expect(lexer::token_type::end_array); - get_token(); if (keep and callback and not callback(--depth, parse_event_t::array_end, result)) { result = basic_json(value_t::discarded); @@ -9349,22 +12720,18 @@ basic_json_parser_66: case lexer::token_type::literal_null: { - get_token(); result.m_type = value_t::null; break; } case lexer::token_type::value_string: { - const auto s = m_lexer.get_string(); - get_token(); - result = basic_json(s); + result = basic_json(m_lexer.get_string()); break; } case lexer::token_type::literal_true: { - get_token(); result.m_type = value_t::boolean; result.m_value = true; break; @@ -9372,16 +12739,36 @@ basic_json_parser_66: case lexer::token_type::literal_false: { - get_token(); result.m_type = value_t::boolean; result.m_value = false; break; } - case lexer::token_type::value_number: + case lexer::token_type::value_unsigned: { - m_lexer.get_number(result); - get_token(); + result.m_type = value_t::number_unsigned; + result.m_value = m_lexer.get_number_unsigned(); + break; + } + + case lexer::token_type::value_integer: + { + result.m_type = value_t::number_integer; + result.m_value = m_lexer.get_number_integer(); + break; + } + + case lexer::token_type::value_float: + { + result.m_type = value_t::number_float; + result.m_value = m_lexer.get_number_float(); + + // throw in case of infinity or NAN + if (JSON_UNLIKELY(not std::isfinite(result.m_value.number_float))) + { + JSON_THROW(out_of_range::create(406, "number overflow parsing '" + m_lexer.get_token_string() + "'")); + } + break; } @@ -9399,6 +12786,130 @@ basic_json_parser_66: return result; } + /*! + @brief the acutal acceptor + + @invariant 1. The last token is not yet processed. Therefore, the + caller of this function must make sure a token has + been read. + 2. When this function returns, the last token is processed. + That is, the last read character was already considered. + + This invariant makes sure that no token needs to be "unput". + */ + bool accept_internal() + { + switch (last_token) + { + case lexer::token_type::begin_object: + { + // read next token + get_token(); + + // closing } -> we are done + if (last_token == lexer::token_type::end_object) + { + return true; + } + + // parse values + while (true) + { + // parse key + if (last_token != lexer::token_type::value_string) + { + return false; + } + + // parse separator (:) + get_token(); + if (last_token != lexer::token_type::name_separator) + { + return false; + } + + // parse value + get_token(); + if (not accept_internal()) + { + return false; + } + + // comma -> next value + get_token(); + if (last_token == lexer::token_type::value_separator) + { + get_token(); + continue; + } + + // closing } + if (last_token != lexer::token_type::end_object) + { + return false; + } + + return true; + } + } + + case lexer::token_type::begin_array: + { + // read next token + get_token(); + + // closing ] -> we are done + if (last_token == lexer::token_type::end_array) + { + return true; + } + + // parse values + while (true) + { + // parse value + if (not accept_internal()) + { + return false; + } + + // comma -> next value + get_token(); + if (last_token == lexer::token_type::value_separator) + { + get_token(); + continue; + } + + // closing ] + if (last_token != lexer::token_type::end_array) + { + return false; + } + + return true; + } + } + + case lexer::token_type::literal_false: + case lexer::token_type::literal_null: + case lexer::token_type::literal_true: + case lexer::token_type::value_float: + case lexer::token_type::value_integer: + case lexer::token_type::value_string: + case lexer::token_type::value_unsigned: + { + return true; + } + + default: + { + // the last token was unexpected + return false; + } + } + } + /// get next token from lexer typename lexer::token_type get_token() { @@ -9406,28 +12917,46 @@ basic_json_parser_66: return last_token; } + /*! + @throw parse_error.101 if expected token did not occur + */ void expect(typename lexer::token_type t) const { - if (t != last_token) + if (JSON_UNLIKELY(t != last_token)) { - std::string error_msg = "parse error - unexpected "; - error_msg += (last_token == lexer::token_type::parse_error ? ("'" + m_lexer.get_token_string() + - "'") : - lexer::token_type_name(last_token)); - error_msg += "; expected " + lexer::token_type_name(t); - throw std::invalid_argument(error_msg); + std::string error_msg = "syntax error - "; + if (last_token == lexer::token_type::parse_error) + { + error_msg += m_lexer.get_error_message() + "; last read: '" + m_lexer.get_token_string() + "'"; + } + else + { + error_msg += "unexpected " + std::string(lexer::token_type_name(last_token)); + } + + error_msg += "; expected " + std::string(lexer::token_type_name(t)); + JSON_THROW(parse_error::create(101, m_lexer.get_position(), error_msg)); } } + /*! + @throw parse_error.101 if unexpected token occurred + */ void unexpect(typename lexer::token_type t) const { - if (t == last_token) + if (JSON_UNLIKELY(t == last_token)) { - std::string error_msg = "parse error - unexpected "; - error_msg += (last_token == lexer::token_type::parse_error ? ("'" + m_lexer.get_token_string() + - "'") : - lexer::token_type_name(last_token)); - throw std::invalid_argument(error_msg); + std::string error_msg = "syntax error - "; + if (last_token == lexer::token_type::parse_error) + { + error_msg += m_lexer.get_error_message() + "; last read '" + m_lexer.get_token_string() + "'"; + } + else + { + error_msg += "unexpected " + std::string(lexer::token_type_name(last_token)); + } + + JSON_THROW(parse_error::create(101, m_lexer.get_position(), error_msg)); } } @@ -9470,12 +12999,12 @@ basic_json_parser_66: empty string is assumed which references the whole JSON value - @throw std::domain_error if reference token is nonempty and does not - begin with a slash (`/`); example: `"JSON pointer must be empty or - begin with /"` - @throw std::domain_error if a tilde (`~`) is not followed by `0` - (representing `~`) or `1` (representing `/`); example: `"escape error: - ~ must be followed with 0 or 1"` + @throw parse_error.107 if the given JSON pointer @a s is nonempty and + does not begin with a slash (`/`); see example below + + @throw parse_error.108 if a tilde (`~`) in the given JSON pointer @a s + is not followed by `0` (representing `~`) or `1` (representing `/`); + see example below @liveexample{The example shows the construction several valid JSON pointers as well as the exceptional behavior.,json_pointer} @@ -9518,12 +13047,15 @@ basic_json_parser_66: } private: - /// remove and return last reference pointer + /*! + @brief remove and return last reference pointer + @throw out_of_range.405 if JSON pointer has no parent + */ std::string pop_back() { if (is_root()) { - throw std::domain_error("JSON pointer has no parent"); + JSON_THROW(out_of_range::create(405, "JSON pointer has no parent")); } auto last = reference_tokens.back(); @@ -9541,7 +13073,7 @@ basic_json_parser_66: { if (is_root()) { - throw std::domain_error("JSON pointer has no parent"); + JSON_THROW(out_of_range::create(405, "JSON pointer has no parent")); } json_pointer result = *this; @@ -9553,6 +13085,9 @@ basic_json_parser_66: @brief create and return a reference to the pointed to value @complexity Linear in the number of reference tokens. + + @throw parse_error.109 if array index is not a number + @throw type_error.313 if value cannot be unflattened */ reference get_and_create(reference j) const { @@ -9589,7 +13124,14 @@ basic_json_parser_66: case value_t::array: { // create an entry in the array - result = &result->operator[](static_cast(std::stoi(reference_token))); + JSON_TRY + { + result = &result->operator[](static_cast(std::stoi(reference_token))); + } + JSON_CATCH (std::invalid_argument&) + { + JSON_THROW(parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } break; } @@ -9602,7 +13144,7 @@ basic_json_parser_66: */ default: { - throw std::domain_error("invalid value to unflatten"); + JSON_THROW(type_error::create(313, "invalid value to unflatten")); } } } @@ -9625,9 +13167,9 @@ basic_json_parser_66: @complexity Linear in the length of the JSON pointer. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.404 if the JSON pointer can not be resolved */ reference get_unchecked(pointer ptr) const { @@ -9641,7 +13183,7 @@ basic_json_parser_66: reference_token.end(), [](const char x) { - return std::isdigit(x); + return (x >= '0' and x <= '9'); }); // change value to array for numbers or "-" or to object @@ -9670,25 +13212,32 @@ basic_json_parser_66: // error condition (cf. RFC 6901, Sect. 4) if (reference_token.size() > 1 and reference_token[0] == '0') { - throw std::domain_error("array index must not begin with '0'"); + JSON_THROW(parse_error::create(106, 0, "array index '" + reference_token + "' must not begin with '0'")); } if (reference_token == "-") { - // explicityly treat "-" as index beyond the end + // explicitly treat "-" as index beyond the end ptr = &ptr->operator[](ptr->m_value.array->size()); } else { // convert array index to number; unchecked access - ptr = &ptr->operator[](static_cast(std::stoi(reference_token))); + JSON_TRY + { + ptr = &ptr->operator[](static_cast(std::stoi(reference_token))); + } + JSON_CATCH (std::invalid_argument&) + { + JSON_THROW(parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } } break; } default: { - throw std::out_of_range("unresolved reference token '" + reference_token + "'"); + JSON_THROW(out_of_range::create(404, "unresolved reference token '" + reference_token + "'")); } } } @@ -9696,6 +13245,12 @@ basic_json_parser_66: return *ptr; } + /*! + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.402 if the array index '-' is used + @throw out_of_range.404 if the JSON pointer can not be resolved + */ reference get_checked(pointer ptr) const { for (const auto& reference_token : reference_tokens) @@ -9714,25 +13269,32 @@ basic_json_parser_66: if (reference_token == "-") { // "-" always fails the range check - throw std::out_of_range("array index '-' (" + - std::to_string(ptr->m_value.array->size()) + - ") is out of range"); + JSON_THROW(out_of_range::create(402, "array index '-' (" + + std::to_string(ptr->m_value.array->size()) + + ") is out of range")); } // error condition (cf. RFC 6901, Sect. 4) if (reference_token.size() > 1 and reference_token[0] == '0') { - throw std::domain_error("array index must not begin with '0'"); + JSON_THROW(parse_error::create(106, 0, "array index '" + reference_token + "' must not begin with '0'")); } // note: at performs range check - ptr = &ptr->at(static_cast(std::stoi(reference_token))); + JSON_TRY + { + ptr = &ptr->at(static_cast(std::stoi(reference_token))); + } + JSON_CATCH (std::invalid_argument&) + { + JSON_THROW(parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } break; } default: { - throw std::out_of_range("unresolved reference token '" + reference_token + "'"); + JSON_THROW(out_of_range::create(404, "unresolved reference token '" + reference_token + "'")); } } } @@ -9747,6 +13309,11 @@ basic_json_parser_66: @return const reference to the JSON value pointed to by the JSON pointer + + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.402 if the array index '-' is used + @throw out_of_range.404 if the JSON pointer can not be resolved */ const_reference get_unchecked(const_pointer ptr) const { @@ -9766,25 +13333,32 @@ basic_json_parser_66: if (reference_token == "-") { // "-" cannot be used for const access - throw std::out_of_range("array index '-' (" + - std::to_string(ptr->m_value.array->size()) + - ") is out of range"); + JSON_THROW(out_of_range::create(402, "array index '-' (" + + std::to_string(ptr->m_value.array->size()) + + ") is out of range")); } // error condition (cf. RFC 6901, Sect. 4) if (reference_token.size() > 1 and reference_token[0] == '0') { - throw std::domain_error("array index must not begin with '0'"); + JSON_THROW(parse_error::create(106, 0, "array index '" + reference_token + "' must not begin with '0'")); } // use unchecked array access - ptr = &ptr->operator[](static_cast(std::stoi(reference_token))); + JSON_TRY + { + ptr = &ptr->operator[](static_cast(std::stoi(reference_token))); + } + JSON_CATCH (std::invalid_argument&) + { + JSON_THROW(parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } break; } default: { - throw std::out_of_range("unresolved reference token '" + reference_token + "'"); + JSON_THROW(out_of_range::create(404, "unresolved reference token '" + reference_token + "'")); } } } @@ -9792,6 +13366,12 @@ basic_json_parser_66: return *ptr; } + /*! + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.402 if the array index '-' is used + @throw out_of_range.404 if the JSON pointer can not be resolved + */ const_reference get_checked(const_pointer ptr) const { for (const auto& reference_token : reference_tokens) @@ -9810,25 +13390,32 @@ basic_json_parser_66: if (reference_token == "-") { // "-" always fails the range check - throw std::out_of_range("array index '-' (" + - std::to_string(ptr->m_value.array->size()) + - ") is out of range"); + JSON_THROW(out_of_range::create(402, "array index '-' (" + + std::to_string(ptr->m_value.array->size()) + + ") is out of range")); } // error condition (cf. RFC 6901, Sect. 4) if (reference_token.size() > 1 and reference_token[0] == '0') { - throw std::domain_error("array index must not begin with '0'"); + JSON_THROW(parse_error::create(106, 0, "array index '" + reference_token + "' must not begin with '0'")); } // note: at performs range check - ptr = &ptr->at(static_cast(std::stoi(reference_token))); + JSON_TRY + { + ptr = &ptr->at(static_cast(std::stoi(reference_token))); + } + JSON_CATCH (std::invalid_argument&) + { + JSON_THROW(parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } break; } default: { - throw std::out_of_range("unresolved reference token '" + reference_token + "'"); + JSON_THROW(out_of_range::create(404, "unresolved reference token '" + reference_token + "'")); } } } @@ -9836,7 +13423,15 @@ basic_json_parser_66: return *ptr; } - /// split the string input to reference tokens + /*! + @brief split the string input to reference tokens + + @note This function is only called by the json_pointer constructor. + All exceptions below are documented there. + + @throw parse_error.107 if the pointer is not empty or begins with '/' + @throw parse_error.108 if character '~' is not followed by '0' or '1' + */ static std::vector split(const std::string& reference_string) { std::vector result; @@ -9850,7 +13445,7 @@ basic_json_parser_66: // check if nonempty reference string begins with slash if (reference_string[0] != '/') { - throw std::domain_error("JSON pointer must be empty or begin with '/'"); + JSON_THROW(parse_error::create(107, 1, "JSON pointer must be empty or begin with '/' - was: '" + reference_string + "'")); } // extract the reference tokens: @@ -9858,7 +13453,7 @@ basic_json_parser_66: // - start: position after the previous slash for ( // search for the first slash after the first character - size_t slash = reference_string.find_first_of("/", 1), + size_t slash = reference_string.find_first_of('/', 1), // set the beginning of the first reference token start = 1; // we can stop if start == string::npos+1 = 0 @@ -9867,16 +13462,16 @@ basic_json_parser_66: // (will eventually be 0 if slash == std::string::npos) start = slash + 1, // find next slash - slash = reference_string.find_first_of("/", start)) + slash = reference_string.find_first_of('/', start)) { // use the text between the beginning of the reference token // (start) and the last slash (slash). auto reference_token = reference_string.substr(start, slash - start); // check reference tokens are properly escaped - for (size_t pos = reference_token.find_first_of("~"); + for (size_t pos = reference_token.find_first_of('~'); pos != std::string::npos; - pos = reference_token.find_first_of("~", pos + 1)) + pos = reference_token.find_first_of('~', pos + 1)) { assert(reference_token[pos] == '~'); @@ -9885,7 +13480,7 @@ basic_json_parser_66: (reference_token[pos + 1] != '0' and reference_token[pos + 1] != '1')) { - throw std::domain_error("escape error: '~' must be followed with '0' or '1'"); + JSON_THROW(parse_error::create(108, 0, "escape character '~' must be followed with '0' or '1'")); } } @@ -9897,18 +13492,16 @@ basic_json_parser_66: return result; } - private: /*! @brief replace all occurrences of a substring by another string - @param[in,out] s the string to manipulate + @param[in,out] s the string to manipulate; changed so that all + occurrences of @a f are replaced with @a t @param[in] f the substring to replace with @a t @param[in] t the string to replace @a f - @return The string @a s where all occurrences of @a f are replaced - with @a t. - - @pre The search string @a f must not be empty. + @pre The search string @a f must not be empty. **This precondition is + enforced with an assertion.** @since version 2.0.0 */ @@ -10008,12 +13601,17 @@ basic_json_parser_66: @param[in] value flattened JSON @return unflattened JSON + + @throw parse_error.109 if array index is not a number + @throw type_error.314 if value is not an object + @throw type_error.315 if object values are not primitive + @throw type_error.313 if value cannot be unflattened */ static basic_json unflatten(const basic_json& value) { if (not value.is_object()) { - throw std::domain_error("only objects can be unflattened"); + JSON_THROW(type_error::create(314, "only objects can be unflattened")); } basic_json result; @@ -10023,7 +13621,7 @@ basic_json_parser_66: { if (not element.second.is_primitive()) { - throw std::domain_error("values in object must be primitive"); + JSON_THROW(type_error::create(315, "values in object must be primitive")); } // assign value to reference pointed to by JSON pointer; Note @@ -10037,7 +13635,18 @@ basic_json_parser_66: return result; } - private: + friend bool operator==(json_pointer const& lhs, + json_pointer const& rhs) noexcept + { + return lhs.reference_tokens == rhs.reference_tokens; + } + + friend bool operator!=(json_pointer const& lhs, + json_pointer const& rhs) noexcept + { + return !(lhs == rhs); + } + /// the reference tokens std::vector reference_tokens {}; }; @@ -10074,9 +13683,9 @@ basic_json_parser_66: @complexity Constant. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.404 if the JSON pointer can not be resolved @liveexample{The behavior is shown in the example.,operatorjson_pointer} @@ -10101,9 +13710,10 @@ basic_json_parser_66: @complexity Constant. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.402 if the array index '-' is used + @throw out_of_range.404 if the JSON pointer can not be resolved @liveexample{The behavior is shown in the example.,operatorjson_pointer_const} @@ -10124,15 +13734,30 @@ basic_json_parser_66: @return reference to the element pointed to by @a ptr - @complexity Constant. + @throw parse_error.106 if an array index in the passed JSON pointer @a ptr + begins with '0'. See example below. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.109 if an array index in the passed JSON pointer @a ptr + is not a number. See example below. - @liveexample{The behavior is shown in the example.,at_json_pointer} + @throw out_of_range.401 if an array index in the passed JSON pointer @a ptr + is out of range. See example below. + + @throw out_of_range.402 if the array index '-' is used in the passed JSON + pointer @a ptr. As `at` provides checked access (and no elements are + implicitly inserted), the index '-' is always invalid. See example below. + + @throw out_of_range.404 if the JSON pointer @a ptr can not be resolved. + See example below. + + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. + + @complexity Constant. @since version 2.0.0 + + @liveexample{The behavior is shown in the example.,at_json_pointer} */ reference at(const json_pointer& ptr) { @@ -10149,15 +13774,30 @@ basic_json_parser_66: @return reference to the element pointed to by @a ptr - @complexity Constant. + @throw parse_error.106 if an array index in the passed JSON pointer @a ptr + begins with '0'. See example below. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.109 if an array index in the passed JSON pointer @a ptr + is not a number. See example below. - @liveexample{The behavior is shown in the example.,at_json_pointer_const} + @throw out_of_range.401 if an array index in the passed JSON pointer @a ptr + is out of range. See example below. + + @throw out_of_range.402 if the array index '-' is used in the passed JSON + pointer @a ptr. As `at` provides checked access (and no elements are + implicitly inserted), the index '-' is always invalid. See example below. + + @throw out_of_range.404 if the JSON pointer @a ptr can not be resolved. + See example below. + + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. + + @complexity Constant. @since version 2.0.0 + + @liveexample{The behavior is shown in the example.,at_json_pointer_const} */ const_reference at(const json_pointer& ptr) const { @@ -10172,7 +13812,7 @@ basic_json_parser_66: primitive. The original JSON value can be restored using the @ref unflatten() function. - @return an object that maps JSON pointers to primitve values + @return an object that maps JSON pointers to primitive values @note Empty objects and arrays are flattened to `null` and will not be reconstructed correctly by the @ref unflatten() function. @@ -10213,6 +13853,9 @@ basic_json_parser_66: @complexity Linear in the size the JSON value. + @throw type_error.314 if value is not an object + @throw type_error.315 if object values are not primitve + @liveexample{The following code shows how a flattened JSON object is unflattened into the original nested JSON object.,unflatten} @@ -10239,7 +13882,7 @@ basic_json_parser_66: [JSON Patch](http://jsonpatch.com) defines a JSON document structure for expressing a sequence of operations to apply to a JSON) document. With - this funcion, a JSON Patch is applied to the current JSON value by + this function, a JSON Patch is applied to the current JSON value by executing all operations from the patch. @param[in] json_patch JSON patch document @@ -10250,12 +13893,23 @@ basic_json_parser_66: any case, the original value is not changed: the patch is applied to a copy of the value. - @throw std::out_of_range if a JSON pointer inside the patch could not - be resolved successfully in the current JSON value; example: `"key baz - not found"` - @throw invalid_argument if the JSON patch is malformed (e.g., mandatory + @throw parse_error.104 if the JSON patch does not consist of an array of + objects + + @throw parse_error.105 if the JSON patch is malformed (e.g., mandatory attributes are missing); example: `"operation add must have member path"` + @throw out_of_range.401 if an array index is out of range. + + @throw out_of_range.403 if a JSON pointer inside the patch could not be + resolved successfully in the current JSON value; example: `"key baz not + found"` + + @throw out_of_range.405 if JSON pointer has no parent ("add", "remove", + "move") + + @throw other_error.501 if "test" operation was unsuccessful + @complexity Linear in the size of the JSON value and the length of the JSON patch. As usually only a fraction of the JSON value is affected by the patch, the complexity can usually be neglected. @@ -10278,7 +13932,7 @@ basic_json_parser_66: // the valid JSON Patch operations enum class patch_operations {add, remove, replace, move, copy, test, invalid}; - const auto get_op = [](const std::string op) + const auto get_op = [](const std::string & op) { if (op == "add") { @@ -10352,7 +14006,7 @@ basic_json_parser_66: if (static_cast(idx) > parent.size()) { // avoid undefined behavior - throw std::out_of_range("array index " + std::to_string(idx) + " is out of range"); + JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range")); } else { @@ -10390,7 +14044,7 @@ basic_json_parser_66: } else { - throw std::out_of_range("key '" + last_path + "' not found"); + JSON_THROW(out_of_range::create(403, "key '" + last_path + "' not found")); } } else if (parent.is_array()) @@ -10400,14 +14054,13 @@ basic_json_parser_66: } }; - // type check + // type check: top level value must be an array if (not json_patch.is_array()) { - // a JSON patch must be an array of objects - throw std::invalid_argument("JSON patch must be an array of objects"); + JSON_THROW(parse_error::create(104, 0, "JSON patch must be an array of objects")); } - // iterate and apply th eoperations + // iterate and apply the operations for (const auto& val : json_patch) { // wrapper to get a value for an operation @@ -10424,23 +14077,23 @@ basic_json_parser_66: // check if desired value is present if (it == val.m_value.object->end()) { - throw std::invalid_argument(error_msg + " must have member '" + member + "'"); + JSON_THROW(parse_error::create(105, 0, error_msg + " must have member '" + member + "'")); } // check if result is of type string if (string_type and not it->second.is_string()) { - throw std::invalid_argument(error_msg + " must have string member '" + member + "'"); + JSON_THROW(parse_error::create(105, 0, error_msg + " must have string member '" + member + "'")); } // no error: return value return it->second; }; - // type check + // type check: every element of the array must be an object if (not val.is_object()) { - throw std::invalid_argument("JSON patch must be an array of objects"); + JSON_THROW(parse_error::create(104, 0, "JSON patch must be an array of objects")); } // collect mandatory members @@ -10499,13 +14152,13 @@ basic_json_parser_66: case patch_operations::test: { bool success = false; - try + JSON_TRY { // check if "value" matches the one at "path" // the "path" location must exist - use at() success = (result.at(ptr) == get_value("test", "value", false)); } - catch (std::out_of_range&) + JSON_CATCH (out_of_range&) { // ignore out of range errors: success remains false } @@ -10513,7 +14166,7 @@ basic_json_parser_66: // throw an exception if test fails if (not success) { - throw std::domain_error("unsuccessful: " + val.dump()); + JSON_THROW(other_error::create(501, "unsuccessful: " + val.dump())); } break; @@ -10523,7 +14176,7 @@ basic_json_parser_66: { // op must be "add", "remove", "replace", "move", "copy", or // "test" - throw std::invalid_argument("operation value '" + op + "' is invalid"); + JSON_THROW(parse_error::create(105, 0, "operation value '" + op + "' is invalid")); } } } @@ -10546,8 +14199,8 @@ basic_json_parser_66: @note Currently, only `remove`, `add`, and `replace` operations are generated. - @param[in] source JSON value to copare from - @param[in] target JSON value to copare against + @param[in] source JSON value to compare from + @param[in] target JSON value to compare against @param[in] path helper value to create JSON pointers @return a JSON patch to convert the @a source to @a target @@ -10698,7 +14351,6 @@ basic_json_parser_66: /// @} }; - ///////////// // presets // ///////////// @@ -10712,7 +14364,7 @@ uses the standard template types. @since version 1.0.0 */ using json = basic_json<>; -} +} // namespace nlohmann /////////////////////// @@ -10753,7 +14405,23 @@ struct hash return h(j.dump()); } }; -} + +/// specialization for std::less +template <> +struct less<::nlohmann::detail::value_t> +{ + /*! + @brief compare two value_t enum values + @since version 3.0.0 + */ + bool operator()(nlohmann::detail::value_t lhs, + nlohmann::detail::value_t rhs) const noexcept + { + return nlohmann::detail::operator<(lhs, rhs); + } +}; + +} // namespace std /*! @brief user-defined string literal for JSON values @@ -10795,5 +14463,16 @@ inline nlohmann::json::json_pointer operator "" _json_pointer(const char* s, std #if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__) #pragma GCC diagnostic pop #endif +#if defined(__clang__) + #pragma GCC diagnostic pop +#endif + +// clean up +#undef JSON_CATCH +#undef JSON_THROW +#undef JSON_TRY +#undef JSON_LIKELY +#undef JSON_UNLIKELY +#undef JSON_DEPRECATED #endif diff --git a/ext/lmdb++.h b/ext/lmdb++.h deleted file mode 100644 index ab75f8c..0000000 --- a/ext/lmdb++.h +++ /dev/null @@ -1,1913 +0,0 @@ -/* This is free and unencumbered software released into the public domain. */ - -#ifndef LMDBXX_H -#define LMDBXX_H - -/** - * - C++11 wrapper for LMDB. - * - * @author Arto Bendiken - * @see https://sourceforge.net/projects/lmdbxx/ - */ - -#ifndef __cplusplus -#error " requires a C++ compiler" -#endif - -#if __cplusplus < 201103L -#if !defined(_MSC_VER) || _MSC_VER < 1900 -#error " requires a C++11 compiler (CXXFLAGS='-std=c++11')" -#endif // _MSC_VER check -#endif - -//////////////////////////////////////////////////////////////////////////////// - -#include /* for MDB_*, mdb_*() */ - -#ifdef LMDBXX_DEBUG -#include /* for assert() */ -#endif -#include /* for std::size_t */ -#include /* for std::snprintf() */ -#include /* for std::strlen() */ -#include /* for std::runtime_error */ -#include /* for std::string */ -#include /* for std::is_pod<> */ - -namespace lmdb { - using mode = mdb_mode_t; -} - -//////////////////////////////////////////////////////////////////////////////// -/* Error Handling */ - -namespace lmdb { - class error; - class logic_error; - class fatal_error; - class runtime_error; - class key_exist_error; - class not_found_error; - class corrupted_error; - class panic_error; - class version_mismatch_error; - class map_full_error; - class bad_dbi_error; -} - -/** - * Base class for LMDB exception conditions. - * - * @see http://symas.com/mdb/doc/group__errors.html - */ -class lmdb::error : public std::runtime_error { -protected: - const int _code; - -public: - /** - * Throws an error based on the given LMDB return code. - */ - [[noreturn]] static inline void raise(const char* origin, int rc); - - /** - * Constructor. - */ - error(const char* const origin, - const int rc) noexcept - : runtime_error{origin}, - _code{rc} {} - - /** - * Returns the underlying LMDB error code. - */ - int code() const noexcept { - return _code; - } - - /** - * Returns the origin of the LMDB error. - */ - const char* origin() const noexcept { - return runtime_error::what(); - } - - /** - * Returns the underlying LMDB error code. - */ - virtual const char* what() const noexcept { - static thread_local char buffer[1024]; - std::snprintf(buffer, sizeof(buffer), - "%s: %s", origin(), ::mdb_strerror(code())); - return buffer; - } -}; - -/** - * Base class for logic error conditions. - */ -class lmdb::logic_error : public lmdb::error { -public: - using error::error; -}; - -/** - * Base class for fatal error conditions. - */ -class lmdb::fatal_error : public lmdb::error { -public: - using error::error; -}; - -/** - * Base class for runtime error conditions. - */ -class lmdb::runtime_error : public lmdb::error { -public: - using error::error; -}; - -/** - * Exception class for `MDB_KEYEXIST` errors. - * - * @see http://symas.com/mdb/doc/group__errors.html#ga05dc5bbcc7da81a7345bd8676e8e0e3b - */ -class lmdb::key_exist_error final : public lmdb::runtime_error { -public: - using runtime_error::runtime_error; -}; - -/** - * Exception class for `MDB_NOTFOUND` errors. - * - * @see http://symas.com/mdb/doc/group__errors.html#gabeb52e4c4be21b329e31c4add1b71926 - */ -class lmdb::not_found_error final : public lmdb::runtime_error { -public: - using runtime_error::runtime_error; -}; - -/** - * Exception class for `MDB_CORRUPTED` errors. - * - * @see http://symas.com/mdb/doc/group__errors.html#gaf8148bf1b85f58e264e57194bafb03ef - */ -class lmdb::corrupted_error final : public lmdb::fatal_error { -public: - using fatal_error::fatal_error; -}; - -/** - * Exception class for `MDB_PANIC` errors. - * - * @see http://symas.com/mdb/doc/group__errors.html#gae37b9aedcb3767faba3de8c1cf6d3473 - */ -class lmdb::panic_error final : public lmdb::fatal_error { -public: - using fatal_error::fatal_error; -}; - -/** - * Exception class for `MDB_VERSION_MISMATCH` errors. - * - * @see http://symas.com/mdb/doc/group__errors.html#ga909b2db047fa90fb0d37a78f86a6f99b - */ -class lmdb::version_mismatch_error final : public lmdb::fatal_error { -public: - using fatal_error::fatal_error; -}; - -/** - * Exception class for `MDB_MAP_FULL` errors. - * - * @see http://symas.com/mdb/doc/group__errors.html#ga0a83370402a060c9175100d4bbfb9f25 - */ -class lmdb::map_full_error final : public lmdb::runtime_error { -public: - using runtime_error::runtime_error; -}; - -/** - * Exception class for `MDB_BAD_DBI` errors. - * - * @since 0.9.14 (2014/09/20) - * @see http://symas.com/mdb/doc/group__errors.html#gab4c82e050391b60a18a5df08d22a7083 - */ -class lmdb::bad_dbi_error final : public lmdb::runtime_error { -public: - using runtime_error::runtime_error; -}; - -inline void -lmdb::error::raise(const char* const origin, - const int rc) { - switch (rc) { - case MDB_KEYEXIST: throw key_exist_error{origin, rc}; - case MDB_NOTFOUND: throw not_found_error{origin, rc}; - case MDB_CORRUPTED: throw corrupted_error{origin, rc}; - case MDB_PANIC: throw panic_error{origin, rc}; - case MDB_VERSION_MISMATCH: throw version_mismatch_error{origin, rc}; - case MDB_MAP_FULL: throw map_full_error{origin, rc}; -#ifdef MDB_BAD_DBI - case MDB_BAD_DBI: throw bad_dbi_error{origin, rc}; -#endif - default: throw lmdb::runtime_error{origin, rc}; - } -} - -//////////////////////////////////////////////////////////////////////////////// -/* Procedural Interface: Metadata */ - -namespace lmdb { - // TODO: mdb_version() - // TODO: mdb_strerror() -} - -//////////////////////////////////////////////////////////////////////////////// -/* Procedural Interface: Environment */ - -namespace lmdb { - static inline void env_create(MDB_env** env); - static inline void env_open(MDB_env* env, - const char* path, unsigned int flags, mode mode); -#if MDB_VERSION_FULL >= MDB_VERINT(0, 9, 14) - static inline void env_copy(MDB_env* env, const char* path, unsigned int flags); - static inline void env_copy_fd(MDB_env* env, mdb_filehandle_t fd, unsigned int flags); -#else - static inline void env_copy(MDB_env* env, const char* path); - static inline void env_copy_fd(MDB_env* env, mdb_filehandle_t fd); -#endif - static inline void env_stat(MDB_env* env, MDB_stat* stat); - static inline void env_info(MDB_env* env, MDB_envinfo* stat); - static inline void env_sync(MDB_env* env, bool force); - static inline void env_close(MDB_env* env) noexcept; - static inline void env_set_flags(MDB_env* env, unsigned int flags, bool onoff); - static inline void env_get_flags(MDB_env* env, unsigned int* flags); - static inline void env_get_path(MDB_env* env, const char** path); - static inline void env_get_fd(MDB_env* env, mdb_filehandle_t* fd); - static inline void env_set_mapsize(MDB_env* env, std::size_t size); - static inline void env_set_max_readers(MDB_env* env, unsigned int count); - static inline void env_get_max_readers(MDB_env* env, unsigned int* count); - static inline void env_set_max_dbs(MDB_env* env, MDB_dbi count); - static inline unsigned int env_get_max_keysize(MDB_env* env); -#if MDB_VERSION_FULL >= MDB_VERINT(0, 9, 11) - static inline void env_set_userctx(MDB_env* env, void* ctx); - static inline void* env_get_userctx(MDB_env* env); -#endif - // TODO: mdb_env_set_assert() - // TODO: mdb_reader_list() - // TODO: mdb_reader_check() -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gaad6be3d8dcd4ea01f8df436f41d158d4 - */ -static inline void -lmdb::env_create(MDB_env** env) { - const int rc = ::mdb_env_create(env); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_create", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga32a193c6bf4d7d5c5d579e71f22e9340 - */ -static inline void -lmdb::env_open(MDB_env* const env, - const char* const path, - const unsigned int flags, - const mode mode) { - const int rc = ::mdb_env_open(env, path, flags, mode); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_open", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga3bf50d7793b36aaddf6b481a44e24244 - * @see http://symas.com/mdb/doc/group__mdb.html#ga5d51d6130325f7353db0955dbedbc378 - */ -static inline void -lmdb::env_copy(MDB_env* const env, -#if MDB_VERSION_FULL >= MDB_VERINT(0, 9, 14) - const char* const path, - const unsigned int flags = 0) { - const int rc = ::mdb_env_copy2(env, path, flags); -#else - const char* const path) { - const int rc = ::mdb_env_copy(env, path); -#endif - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_copy2", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga5040d0de1f14000fa01fc0b522ff1f86 - * @see http://symas.com/mdb/doc/group__mdb.html#ga470b0bcc64ac417de5de5930f20b1a28 - */ -static inline void -lmdb::env_copy_fd(MDB_env* const env, -#if MDB_VERSION_FULL >= MDB_VERINT(0, 9, 14) - const mdb_filehandle_t fd, - const unsigned int flags = 0) { - const int rc = ::mdb_env_copyfd2(env, fd, flags); -#else - const mdb_filehandle_t fd) { - const int rc = ::mdb_env_copyfd(env, fd); -#endif - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_copyfd2", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gaf881dca452050efbd434cd16e4bae255 - */ -static inline void -lmdb::env_stat(MDB_env* const env, - MDB_stat* const stat) { - const int rc = ::mdb_env_stat(env, stat); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_stat", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga18769362c7e7d6cf91889a028a5c5947 - */ -static inline void -lmdb::env_info(MDB_env* const env, - MDB_envinfo* const stat) { - const int rc = ::mdb_env_info(env, stat); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_info", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga85e61f05aa68b520cc6c3b981dba5037 - */ -static inline void -lmdb::env_sync(MDB_env* const env, - const bool force = true) { - const int rc = ::mdb_env_sync(env, force); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_sync", rc); - } -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#ga4366c43ada8874588b6a62fbda2d1e95 - */ -static inline void -lmdb::env_close(MDB_env* const env) noexcept { - ::mdb_env_close(env); -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga83f66cf02bfd42119451e9468dc58445 - */ -static inline void -lmdb::env_set_flags(MDB_env* const env, - const unsigned int flags, - const bool onoff = true) { - const int rc = ::mdb_env_set_flags(env, flags, onoff ? 1 : 0); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_set_flags", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga2733aefc6f50beb49dd0c6eb19b067d9 - */ -static inline void -lmdb::env_get_flags(MDB_env* const env, - unsigned int* const flags) { - const int rc = ::mdb_env_get_flags(env, flags); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_get_flags", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gac699fdd8c4f8013577cb933fb6a757fe - */ -static inline void -lmdb::env_get_path(MDB_env* const env, - const char** path) { - const int rc = ::mdb_env_get_path(env, path); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_get_path", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gaf1570e7c0e5a5d860fef1032cec7d5f2 - */ -static inline void -lmdb::env_get_fd(MDB_env* const env, - mdb_filehandle_t* const fd) { - const int rc = ::mdb_env_get_fd(env, fd); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_get_fd", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gaa2506ec8dab3d969b0e609cd82e619e5 - */ -static inline void -lmdb::env_set_mapsize(MDB_env* const env, - const std::size_t size) { - const int rc = ::mdb_env_set_mapsize(env, size); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_set_mapsize", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gae687966c24b790630be2a41573fe40e2 - */ -static inline void -lmdb::env_set_max_readers(MDB_env* const env, - const unsigned int count) { - const int rc = ::mdb_env_set_maxreaders(env, count); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_set_maxreaders", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga70e143cf11760d869f754c9c9956e6cc - */ -static inline void -lmdb::env_get_max_readers(MDB_env* const env, - unsigned int* const count) { - const int rc = ::mdb_env_get_maxreaders(env, count); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_get_maxreaders", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gaa2fc2f1f37cb1115e733b62cab2fcdbc - */ -static inline void -lmdb::env_set_max_dbs(MDB_env* const env, - const MDB_dbi count) { - const int rc = ::mdb_env_set_maxdbs(env, count); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_set_maxdbs", rc); - } -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#gaaf0be004f33828bf2fb09d77eb3cef94 - */ -static inline unsigned int -lmdb::env_get_max_keysize(MDB_env* const env) { - const int rc = ::mdb_env_get_maxkeysize(env); -#ifdef LMDBXX_DEBUG - assert(rc >= 0); -#endif - return static_cast(rc); -} - -#if MDB_VERSION_FULL >= MDB_VERINT(0, 9, 11) -/** - * @throws lmdb::error on failure - * @since 0.9.11 (2014/01/15) - * @see http://symas.com/mdb/doc/group__mdb.html#gaf2fe09eb9c96eeb915a76bf713eecc46 - */ -static inline void -lmdb::env_set_userctx(MDB_env* const env, - void* const ctx) { - const int rc = ::mdb_env_set_userctx(env, ctx); - if (rc != MDB_SUCCESS) { - error::raise("mdb_env_set_userctx", rc); - } -} -#endif - -#if MDB_VERSION_FULL >= MDB_VERINT(0, 9, 11) -/** - * @since 0.9.11 (2014/01/15) - * @see http://symas.com/mdb/doc/group__mdb.html#ga45df6a4fb150cda2316b5ae224ba52f1 - */ -static inline void* -lmdb::env_get_userctx(MDB_env* const env) { - return ::mdb_env_get_userctx(env); -} -#endif - -//////////////////////////////////////////////////////////////////////////////// -/* Procedural Interface: Transactions */ - -namespace lmdb { - static inline void txn_begin( - MDB_env* env, MDB_txn* parent, unsigned int flags, MDB_txn** txn); - static inline MDB_env* txn_env(MDB_txn* txn) noexcept; -#ifdef LMDBXX_TXN_ID - static inline std::size_t txn_id(MDB_txn* txn) noexcept; -#endif - static inline void txn_commit(MDB_txn* txn); - static inline void txn_abort(MDB_txn* txn) noexcept; - static inline void txn_reset(MDB_txn* txn) noexcept; - static inline void txn_renew(MDB_txn* txn); -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gad7ea55da06b77513609efebd44b26920 - */ -static inline void -lmdb::txn_begin(MDB_env* const env, - MDB_txn* const parent, - const unsigned int flags, - MDB_txn** txn) { - const int rc = ::mdb_txn_begin(env, parent, flags, txn); - if (rc != MDB_SUCCESS) { - error::raise("mdb_txn_begin", rc); - } -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#gaeb17735b8aaa2938a78a45cab85c06a0 - */ -static inline MDB_env* -lmdb::txn_env(MDB_txn* const txn) noexcept { - return ::mdb_txn_env(txn); -} - -#ifdef LMDBXX_TXN_ID -/** - * @note Only available in HEAD, not yet in any 0.9.x release (as of 0.9.16). - */ -static inline std::size_t -lmdb::txn_id(MDB_txn* const txn) noexcept { - return ::mdb_txn_id(txn); -} -#endif - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga846fbd6f46105617ac9f4d76476f6597 - */ -static inline void -lmdb::txn_commit(MDB_txn* const txn) { - const int rc = ::mdb_txn_commit(txn); - if (rc != MDB_SUCCESS) { - error::raise("mdb_txn_commit", rc); - } -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#ga73a5938ae4c3239ee11efa07eb22b882 - */ -static inline void -lmdb::txn_abort(MDB_txn* const txn) noexcept { - ::mdb_txn_abort(txn); -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#ga02b06706f8a66249769503c4e88c56cd - */ -static inline void -lmdb::txn_reset(MDB_txn* const txn) noexcept { - ::mdb_txn_reset(txn); -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga6c6f917959517ede1c504cf7c720ce6d - */ -static inline void -lmdb::txn_renew(MDB_txn* const txn) { - const int rc = ::mdb_txn_renew(txn); - if (rc != MDB_SUCCESS) { - error::raise("mdb_txn_renew", rc); - } -} - -//////////////////////////////////////////////////////////////////////////////// -/* Procedural Interface: Databases */ - -namespace lmdb { - static inline void dbi_open( - MDB_txn* txn, const char* name, unsigned int flags, MDB_dbi* dbi); - static inline void dbi_stat(MDB_txn* txn, MDB_dbi dbi, MDB_stat* stat); - static inline void dbi_flags(MDB_txn* txn, MDB_dbi dbi, unsigned int* flags); - static inline void dbi_close(MDB_env* env, MDB_dbi dbi) noexcept; - static inline void dbi_drop(MDB_txn* txn, MDB_dbi dbi, bool del); - static inline void dbi_set_compare(MDB_txn* txn, MDB_dbi dbi, MDB_cmp_func* cmp); - static inline void dbi_set_dupsort(MDB_txn* txn, MDB_dbi dbi, MDB_cmp_func* cmp); - static inline void dbi_set_relfunc(MDB_txn* txn, MDB_dbi dbi, MDB_rel_func* rel); - static inline void dbi_set_relctx(MDB_txn* txn, MDB_dbi dbi, void* ctx); - static inline bool dbi_get(MDB_txn* txn, MDB_dbi dbi, const MDB_val* key, MDB_val* data); - static inline bool dbi_put(MDB_txn* txn, MDB_dbi dbi, const MDB_val* key, MDB_val* data, unsigned int flags); - static inline bool dbi_del(MDB_txn* txn, MDB_dbi dbi, const MDB_val* key, const MDB_val* data); - // TODO: mdb_cmp() - // TODO: mdb_dcmp() -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gac08cad5b096925642ca359a6d6f0562a - */ -static inline void -lmdb::dbi_open(MDB_txn* const txn, - const char* const name, - const unsigned int flags, - MDB_dbi* const dbi) { - const int rc = ::mdb_dbi_open(txn, name, flags, dbi); - if (rc != MDB_SUCCESS) { - error::raise("mdb_dbi_open", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gae6c1069febe94299769dbdd032fadef6 - */ -static inline void -lmdb::dbi_stat(MDB_txn* const txn, - const MDB_dbi dbi, - MDB_stat* const result) { - const int rc = ::mdb_stat(txn, dbi, result); - if (rc != MDB_SUCCESS) { - error::raise("mdb_stat", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga95ba4cb721035478a8705e57b91ae4d4 - */ -static inline void -lmdb::dbi_flags(MDB_txn* const txn, - const MDB_dbi dbi, - unsigned int* const flags) { - const int rc = ::mdb_dbi_flags(txn, dbi, flags); - if (rc != MDB_SUCCESS) { - error::raise("mdb_dbi_flags", rc); - } -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#ga52dd98d0c542378370cd6b712ff961b5 - */ -static inline void -lmdb::dbi_close(MDB_env* const env, - const MDB_dbi dbi) noexcept { - ::mdb_dbi_close(env, dbi); -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#gab966fab3840fc54a6571dfb32b00f2db - */ -static inline void -lmdb::dbi_drop(MDB_txn* const txn, - const MDB_dbi dbi, - const bool del = false) { - const int rc = ::mdb_drop(txn, dbi, del ? 1 : 0); - if (rc != MDB_SUCCESS) { - error::raise("mdb_drop", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga68e47ffcf72eceec553c72b1784ee0fe - */ -static inline void -lmdb::dbi_set_compare(MDB_txn* const txn, - const MDB_dbi dbi, - MDB_cmp_func* const cmp = nullptr) { - const int rc = ::mdb_set_compare(txn, dbi, cmp); - if (rc != MDB_SUCCESS) { - error::raise("mdb_set_compare", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gacef4ec3dab0bbd9bc978b73c19c879ae - */ -static inline void -lmdb::dbi_set_dupsort(MDB_txn* const txn, - const MDB_dbi dbi, - MDB_cmp_func* const cmp = nullptr) { - const int rc = ::mdb_set_dupsort(txn, dbi, cmp); - if (rc != MDB_SUCCESS) { - error::raise("mdb_set_dupsort", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga697d82c7afe79f142207ad5adcdebfeb - */ -static inline void -lmdb::dbi_set_relfunc(MDB_txn* const txn, - const MDB_dbi dbi, - MDB_rel_func* const rel) { - const int rc = ::mdb_set_relfunc(txn, dbi, rel); - if (rc != MDB_SUCCESS) { - error::raise("mdb_set_relfunc", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga7c34246308cee01724a1839a8f5cc594 - */ -static inline void -lmdb::dbi_set_relctx(MDB_txn* const txn, - const MDB_dbi dbi, - void* const ctx) { - const int rc = ::mdb_set_relctx(txn, dbi, ctx); - if (rc != MDB_SUCCESS) { - error::raise("mdb_set_relctx", rc); - } -} - -/** - * @retval true if the key/value pair was retrieved - * @retval false if the key wasn't found - * @see http://symas.com/mdb/doc/group__mdb.html#ga8bf10cd91d3f3a83a34d04ce6b07992d - */ -static inline bool -lmdb::dbi_get(MDB_txn* const txn, - const MDB_dbi dbi, - const MDB_val* const key, - MDB_val* const data) { - const int rc = ::mdb_get(txn, dbi, const_cast(key), data); - if (rc != MDB_SUCCESS && rc != MDB_NOTFOUND) { - error::raise("mdb_get", rc); - } - return (rc == MDB_SUCCESS); -} - -/** - * @retval true if the key/value pair was inserted - * @retval false if the key already existed - * @see http://symas.com/mdb/doc/group__mdb.html#ga4fa8573d9236d54687c61827ebf8cac0 - */ -static inline bool -lmdb::dbi_put(MDB_txn* const txn, - const MDB_dbi dbi, - const MDB_val* const key, - MDB_val* const data, - const unsigned int flags = 0) { - const int rc = ::mdb_put(txn, dbi, const_cast(key), data, flags); - if (rc != MDB_SUCCESS && rc != MDB_KEYEXIST) { - error::raise("mdb_put", rc); - } - return (rc == MDB_SUCCESS); -} - -/** - * @retval true if the key/value pair was removed - * @retval false if the key wasn't found - * @see http://symas.com/mdb/doc/group__mdb.html#gab8182f9360ea69ac0afd4a4eaab1ddb0 - */ -static inline bool -lmdb::dbi_del(MDB_txn* const txn, - const MDB_dbi dbi, - const MDB_val* const key, - const MDB_val* const data = nullptr) { - const int rc = ::mdb_del(txn, dbi, const_cast(key), const_cast(data)); - if (rc != MDB_SUCCESS && rc != MDB_NOTFOUND) { - error::raise("mdb_del", rc); - } - return (rc == MDB_SUCCESS); -} - -//////////////////////////////////////////////////////////////////////////////// -/* Procedural Interface: Cursors */ - -namespace lmdb { - static inline void cursor_open(MDB_txn* txn, MDB_dbi dbi, MDB_cursor** cursor); - static inline void cursor_close(MDB_cursor* cursor) noexcept; - static inline void cursor_renew(MDB_txn* txn, MDB_cursor* cursor); - static inline MDB_txn* cursor_txn(MDB_cursor* cursor) noexcept; - static inline MDB_dbi cursor_dbi(MDB_cursor* cursor) noexcept; - static inline bool cursor_get(MDB_cursor* cursor, MDB_val* key, MDB_val* data, MDB_cursor_op op); - static inline void cursor_put(MDB_cursor* cursor, MDB_val* key, MDB_val* data, unsigned int flags); - static inline void cursor_del(MDB_cursor* cursor, unsigned int flags); - static inline void cursor_count(MDB_cursor* cursor, std::size_t& count); -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga9ff5d7bd42557fd5ee235dc1d62613aa - */ -static inline void -lmdb::cursor_open(MDB_txn* const txn, - const MDB_dbi dbi, - MDB_cursor** const cursor) { - const int rc = ::mdb_cursor_open(txn, dbi, cursor); - if (rc != MDB_SUCCESS) { - error::raise("mdb_cursor_open", rc); - } -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#gad685f5d73c052715c7bd859cc4c05188 - */ -static inline void -lmdb::cursor_close(MDB_cursor* const cursor) noexcept { - ::mdb_cursor_close(cursor); -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#gac8b57befb68793070c85ea813df481af - */ -static inline void -lmdb::cursor_renew(MDB_txn* const txn, - MDB_cursor* const cursor) { - const int rc = ::mdb_cursor_renew(txn, cursor); - if (rc != MDB_SUCCESS) { - error::raise("mdb_cursor_renew", rc); - } -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#ga7bf0d458f7f36b5232fcb368ebda79e0 - */ -static inline MDB_txn* -lmdb::cursor_txn(MDB_cursor* const cursor) noexcept { - return ::mdb_cursor_txn(cursor); -} - -/** - * @see http://symas.com/mdb/doc/group__mdb.html#ga2f7092cf70ee816fb3d2c3267a732372 - */ -static inline MDB_dbi -lmdb::cursor_dbi(MDB_cursor* const cursor) noexcept { - return ::mdb_cursor_dbi(cursor); -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga48df35fb102536b32dfbb801a47b4cb0 - */ -static inline bool -lmdb::cursor_get(MDB_cursor* const cursor, - MDB_val* const key, - MDB_val* const data, - const MDB_cursor_op op) { - const int rc = ::mdb_cursor_get(cursor, key, data, op); - if (rc != MDB_SUCCESS && rc != MDB_NOTFOUND) { - error::raise("mdb_cursor_get", rc); - } - return (rc == MDB_SUCCESS); -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga1f83ccb40011837ff37cc32be01ad91e - */ -static inline void -lmdb::cursor_put(MDB_cursor* const cursor, - MDB_val* const key, - MDB_val* const data, - const unsigned int flags = 0) { - const int rc = ::mdb_cursor_put(cursor, key, data, flags); - if (rc != MDB_SUCCESS) { - error::raise("mdb_cursor_put", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga26a52d3efcfd72e5bf6bd6960bf75f95 - */ -static inline void -lmdb::cursor_del(MDB_cursor* const cursor, - const unsigned int flags = 0) { - const int rc = ::mdb_cursor_del(cursor, flags); - if (rc != MDB_SUCCESS) { - error::raise("mdb_cursor_del", rc); - } -} - -/** - * @throws lmdb::error on failure - * @see http://symas.com/mdb/doc/group__mdb.html#ga4041fd1e1862c6b7d5f10590b86ffbe2 - */ -static inline void -lmdb::cursor_count(MDB_cursor* const cursor, - std::size_t& count) { - const int rc = ::mdb_cursor_count(cursor, &count); - if (rc != MDB_SUCCESS) { - error::raise("mdb_cursor_count", rc); - } -} - -//////////////////////////////////////////////////////////////////////////////// -/* Resource Interface: Values */ - -namespace lmdb { - class val; -} - -/** - * Wrapper class for `MDB_val` structures. - * - * @note Instances of this class are movable and copyable both. - * @see http://symas.com/mdb/doc/group__mdb.html#structMDB__val - */ -class lmdb::val { -protected: - MDB_val _val; - -public: - /** - * Default constructor. - */ - val() noexcept = default; - - /** - * Constructor. - */ - val(const std::string& data) noexcept - : val{data.data(), data.size()} {} - - /** - * Constructor. - */ - val(const char* const data) noexcept - : val{data, std::strlen(data)} {} - - /** - * Constructor. - */ - val(const void* const data, - const std::size_t size) noexcept - : _val{size, const_cast(data)} {} - - /** - * Move constructor. - */ - val(val&& other) noexcept = default; - - /** - * Move assignment operator. - */ - val& operator=(val&& other) noexcept = default; - - /** - * Destructor. - */ - ~val() noexcept = default; - - /** - * Returns an `MDB_val*` pointer. - */ - operator MDB_val*() noexcept { - return &_val; - } - - /** - * Returns an `MDB_val*` pointer. - */ - operator const MDB_val*() const noexcept { - return &_val; - } - - /** - * Determines whether this value is empty. - */ - bool empty() const noexcept { - return size() == 0; - } - - /** - * Returns the size of the data. - */ - std::size_t size() const noexcept { - return _val.mv_size; - } - - /** - * Returns a pointer to the data. - */ - template - T* data() noexcept { - return reinterpret_cast(_val.mv_data); - } - - /** - * Returns a pointer to the data. - */ - template - const T* data() const noexcept { - return reinterpret_cast(_val.mv_data); - } - - /** - * Returns a pointer to the data. - */ - char* data() noexcept { - return reinterpret_cast(_val.mv_data); - } - - /** - * Returns a pointer to the data. - */ - const char* data() const noexcept { - return reinterpret_cast(_val.mv_data); - } - - /** - * Assigns the value. - */ - template - val& assign(const T* const data, - const std::size_t size) noexcept { - _val.mv_size = size; - _val.mv_data = const_cast(reinterpret_cast(data)); - return *this; - } - - /** - * Assigns the value. - */ - val& assign(const char* const data) noexcept { - return assign(data, std::strlen(data)); - } - - /** - * Assigns the value. - */ - val& assign(const std::string& data) noexcept { - return assign(data.data(), data.size()); - } -}; - -#if !(defined(__COVERITY__) || defined(_MSC_VER)) -static_assert(std::is_pod::value, "lmdb::val must be a POD type"); -static_assert(sizeof(lmdb::val) == sizeof(MDB_val), "sizeof(lmdb::val) != sizeof(MDB_val)"); -#endif - -//////////////////////////////////////////////////////////////////////////////// -/* Resource Interface: Environment */ - -namespace lmdb { - class env; -} - -/** - * Resource class for `MDB_env*` handles. - * - * @note Instances of this class are movable, but not copyable. - * @see http://symas.com/mdb/doc/group__internal.html#structMDB__env - */ -class lmdb::env { -protected: - MDB_env* _handle{nullptr}; - -public: - static constexpr unsigned int default_flags = 0; - static constexpr mode default_mode = 0644; /* -rw-r--r-- */ - - /** - * Creates a new LMDB environment. - * - * @param flags - * @throws lmdb::error on failure - */ - static env create(const unsigned int flags = default_flags) { - MDB_env* handle{nullptr}; - lmdb::env_create(&handle); -#ifdef LMDBXX_DEBUG - assert(handle != nullptr); -#endif - if (flags) { - try { - lmdb::env_set_flags(handle, flags); - } - catch (const lmdb::error&) { - lmdb::env_close(handle); - throw; - } - } - return env{handle}; - } - - /** - * Constructor. - * - * @param handle a valid `MDB_env*` handle - */ - env(MDB_env* const handle) noexcept - : _handle{handle} {} - - /** - * Move constructor. - */ - env(env&& other) noexcept { - std::swap(_handle, other._handle); - } - - /** - * Move assignment operator. - */ - env& operator=(env&& other) noexcept { - if (this != &other) { - std::swap(_handle, other._handle); - } - return *this; - } - - /** - * Destructor. - */ - ~env() noexcept { - try { close(); } catch (...) {} - } - - /** - * Returns the underlying `MDB_env*` handle. - */ - operator MDB_env*() const noexcept { - return _handle; - } - - /** - * Returns the underlying `MDB_env*` handle. - */ - MDB_env* handle() const noexcept { - return _handle; - } - - /** - * Flushes data buffers to disk. - * - * @param force - * @throws lmdb::error on failure - */ - void sync(const bool force = true) { - lmdb::env_sync(handle(), force); - } - - /** - * Closes this environment, releasing the memory map. - * - * @note this method is idempotent - * @post `handle() == nullptr` - */ - void close() noexcept { - if (handle()) { - lmdb::env_close(handle()); - _handle = nullptr; - } - } - - /** - * Opens this environment. - * - * @param path - * @param flags - * @param mode - * @throws lmdb::error on failure - */ - env& open(const char* const path, - const unsigned int flags = default_flags, - const mode mode = default_mode) { - lmdb::env_open(handle(), path, flags, mode); - return *this; - } - - /** - * @param flags - * @param onoff - * @throws lmdb::error on failure - */ - env& set_flags(const unsigned int flags, - const bool onoff = true) { - lmdb::env_set_flags(handle(), flags, onoff); - return *this; - } - - /** - * @param size - * @throws lmdb::error on failure - */ - env& set_mapsize(const std::size_t size) { - lmdb::env_set_mapsize(handle(), size); - return *this; - } - - /** - * @param count - * @throws lmdb::error on failure - */ - env& set_max_readers(const unsigned int count) { - lmdb::env_set_max_readers(handle(), count); - return *this; - } - - /** - * @param count - * @throws lmdb::error on failure - */ - env& set_max_dbs(const MDB_dbi count) { - lmdb::env_set_max_dbs(handle(), count); - return *this; - } -}; - -//////////////////////////////////////////////////////////////////////////////// -/* Resource Interface: Transactions */ - -namespace lmdb { - class txn; -} - -/** - * Resource class for `MDB_txn*` handles. - * - * @note Instances of this class are movable, but not copyable. - * @see http://symas.com/mdb/doc/group__internal.html#structMDB__txn - */ -class lmdb::txn { -protected: - MDB_txn* _handle{nullptr}; - -public: - static constexpr unsigned int default_flags = 0; - - /** - * Creates a new LMDB transaction. - * - * @param env the environment handle - * @param parent - * @param flags - * @throws lmdb::error on failure - */ - static txn begin(MDB_env* const env, - MDB_txn* const parent = nullptr, - const unsigned int flags = default_flags) { - MDB_txn* handle{nullptr}; - lmdb::txn_begin(env, parent, flags, &handle); -#ifdef LMDBXX_DEBUG - assert(handle != nullptr); -#endif - return txn{handle}; - } - - /** - * Constructor. - * - * @param handle a valid `MDB_txn*` handle - */ - txn(MDB_txn* const handle) noexcept - : _handle{handle} {} - - /** - * Move constructor. - */ - txn(txn&& other) noexcept { - std::swap(_handle, other._handle); - } - - /** - * Move assignment operator. - */ - txn& operator=(txn&& other) noexcept { - if (this != &other) { - std::swap(_handle, other._handle); - } - return *this; - } - - /** - * Destructor. - */ - ~txn() noexcept { - if (_handle) { - try { abort(); } catch (...) {} - _handle = nullptr; - } - } - - /** - * Returns the underlying `MDB_txn*` handle. - */ - operator MDB_txn*() const noexcept { - return _handle; - } - - /** - * Returns the underlying `MDB_txn*` handle. - */ - MDB_txn* handle() const noexcept { - return _handle; - } - - /** - * Returns the transaction's `MDB_env*` handle. - */ - MDB_env* env() const noexcept { - return lmdb::txn_env(handle()); - } - - /** - * Commits this transaction. - * - * @throws lmdb::error on failure - * @post `handle() == nullptr` - */ - void commit() { - lmdb::txn_commit(_handle); - _handle = nullptr; - } - - /** - * Aborts this transaction. - * - * @post `handle() == nullptr` - */ - void abort() noexcept { - lmdb::txn_abort(_handle); - _handle = nullptr; - } - - /** - * Resets this read-only transaction. - */ - void reset() noexcept { - lmdb::txn_reset(_handle); - } - - /** - * Renews this read-only transaction. - * - * @throws lmdb::error on failure - */ - void renew() { - lmdb::txn_renew(_handle); - } -}; - -//////////////////////////////////////////////////////////////////////////////// -/* Resource Interface: Databases */ - -namespace lmdb { - class dbi; -} - -/** - * Resource class for `MDB_dbi` handles. - * - * @note Instances of this class are movable, but not copyable. - * @see http://symas.com/mdb/doc/group__mdb.html#gadbe68a06c448dfb62da16443d251a78b - */ -class lmdb::dbi { -protected: - MDB_dbi _handle{0}; - -public: - static constexpr unsigned int default_flags = 0; - static constexpr unsigned int default_put_flags = 0; - - /** - * Opens a database handle. - * - * @param txn the transaction handle - * @param name - * @param flags - * @throws lmdb::error on failure - */ - static dbi - open(MDB_txn* const txn, - const char* const name = nullptr, - const unsigned int flags = default_flags) { - MDB_dbi handle{}; - lmdb::dbi_open(txn, name, flags, &handle); - return dbi{handle}; - } - - /** - * Constructor. - * - * @param handle a valid `MDB_dbi` handle - */ - dbi(const MDB_dbi handle) noexcept - : _handle{handle} {} - - /** - * Move constructor. - */ - dbi(dbi&& other) noexcept { - std::swap(_handle, other._handle); - } - - /** - * Move assignment operator. - */ - dbi& operator=(dbi&& other) noexcept { - if (this != &other) { - std::swap(_handle, other._handle); - } - return *this; - } - - /** - * Destructor. - */ - ~dbi() noexcept { - if (_handle) { - /* No need to call close() here. */ - } - } - - /** - * Returns the underlying `MDB_dbi` handle. - */ - operator MDB_dbi() const noexcept { - return _handle; - } - - /** - * Returns the underlying `MDB_dbi` handle. - */ - MDB_dbi handle() const noexcept { - return _handle; - } - - /** - * Returns statistics for this database. - * - * @param txn a transaction handle - * @throws lmdb::error on failure - */ - MDB_stat stat(MDB_txn* const txn) const { - MDB_stat result; - lmdb::dbi_stat(txn, handle(), &result); - return result; - } - - /** - * Retrieves the flags for this database handle. - * - * @param txn a transaction handle - * @throws lmdb::error on failure - */ - unsigned int flags(MDB_txn* const txn) const { - unsigned int result{}; - lmdb::dbi_flags(txn, handle(), &result); - return result; - } - - /** - * Returns the number of records in this database. - * - * @param txn a transaction handle - * @throws lmdb::error on failure - */ - std::size_t size(MDB_txn* const txn) const { - return stat(txn).ms_entries; - } - - /** - * @param txn a transaction handle - * @param del - * @throws lmdb::error on failure - */ - void drop(MDB_txn* const txn, - const bool del = false) { - lmdb::dbi_drop(txn, handle(), del); - } - - /** - * Sets a custom key comparison function for this database. - * - * @param txn a transaction handle - * @param cmp the comparison function - * @throws lmdb::error on failure - */ - dbi& set_compare(MDB_txn* const txn, - MDB_cmp_func* const cmp = nullptr) { - lmdb::dbi_set_compare(txn, handle(), cmp); - return *this; - } - - /** - * Retrieves a key/value pair from this database. - * - * @param txn a transaction handle - * @param key - * @param data - * @throws lmdb::error on failure - */ - bool get(MDB_txn* const txn, - const val& key, - val& data) { - return lmdb::dbi_get(txn, handle(), key, data); - } - - /** - * Retrieves a key from this database. - * - * @param txn a transaction handle - * @param key - * @throws lmdb::error on failure - */ - template - bool get(MDB_txn* const txn, - const K& key) const { - const lmdb::val k{&key, sizeof(K)}; - lmdb::val v{}; - return lmdb::dbi_get(txn, handle(), k, v); - } - - /** - * Retrieves a key/value pair from this database. - * - * @param txn a transaction handle - * @param key - * @param val - * @throws lmdb::error on failure - */ - template - bool get(MDB_txn* const txn, - const K& key, - V& val) const { - const lmdb::val k{&key, sizeof(K)}; - lmdb::val v{}; - const bool result = lmdb::dbi_get(txn, handle(), k, v); - if (result) { - val = *v.data(); - } - return result; - } - - /** - * Retrieves a key/value pair from this database. - * - * @param txn a transaction handle - * @param key a NUL-terminated string key - * @param val - * @throws lmdb::error on failure - */ - template - bool get(MDB_txn* const txn, - const char* const key, - V& val) const { - const lmdb::val k{key, std::strlen(key)}; - lmdb::val v{}; - const bool result = lmdb::dbi_get(txn, handle(), k, v); - if (result) { - val = *v.data(); - } - return result; - } - - /** - * Stores a key/value pair into this database. - * - * @param txn a transaction handle - * @param key - * @param data - * @param flags - * @throws lmdb::error on failure - */ - bool put(MDB_txn* const txn, - const val& key, - val& data, - const unsigned int flags = default_put_flags) { - return lmdb::dbi_put(txn, handle(), key, data, flags); - } - - /** - * Stores a key into this database. - * - * @param txn a transaction handle - * @param key - * @param flags - * @throws lmdb::error on failure - */ - template - bool put(MDB_txn* const txn, - const K& key, - const unsigned int flags = default_put_flags) { - const lmdb::val k{&key, sizeof(K)}; - lmdb::val v{}; - return lmdb::dbi_put(txn, handle(), k, v, flags); - } - - /** - * Stores a key/value pair into this database. - * - * @param txn a transaction handle - * @param key - * @param val - * @param flags - * @throws lmdb::error on failure - */ - template - bool put(MDB_txn* const txn, - const K& key, - const V& val, - const unsigned int flags = default_put_flags) { - const lmdb::val k{&key, sizeof(K)}; - lmdb::val v{&val, sizeof(V)}; - return lmdb::dbi_put(txn, handle(), k, v, flags); - } - - /** - * Stores a key/value pair into this database. - * - * @param txn a transaction handle - * @param key a NUL-terminated string key - * @param val - * @param flags - * @throws lmdb::error on failure - */ - template - bool put(MDB_txn* const txn, - const char* const key, - const V& val, - const unsigned int flags = default_put_flags) { - const lmdb::val k{key, std::strlen(key)}; - lmdb::val v{&val, sizeof(V)}; - return lmdb::dbi_put(txn, handle(), k, v, flags); - } - - /** - * Stores a key/value pair into this database. - * - * @param txn a transaction handle - * @param key a NUL-terminated string key - * @param val a NUL-terminated string key - * @param flags - * @throws lmdb::error on failure - */ - bool put(MDB_txn* const txn, - const char* const key, - const char* const val, - const unsigned int flags = default_put_flags) { - const lmdb::val k{key, std::strlen(key)}; - lmdb::val v{val, std::strlen(val)}; - return lmdb::dbi_put(txn, handle(), k, v, flags); - } - - /** - * Removes a key/value pair from this database. - * - * @param txn a transaction handle - * @param key - * @throws lmdb::error on failure - */ - bool del(MDB_txn* const txn, - const val& key) { - return lmdb::dbi_del(txn, handle(), key); - } - - /** - * Removes a key/value pair from this database. - * - * @param txn a transaction handle - * @param key - * @throws lmdb::error on failure - */ - template - bool del(MDB_txn* const txn, - const K& key) { - const lmdb::val k{&key, sizeof(K)}; - return lmdb::dbi_del(txn, handle(), k); - } -}; - -//////////////////////////////////////////////////////////////////////////////// -/* Resource Interface: Cursors */ - -namespace lmdb { - class cursor; -} - -/** - * Resource class for `MDB_cursor*` handles. - * - * @note Instances of this class are movable, but not copyable. - * @see http://symas.com/mdb/doc/group__internal.html#structMDB__cursor - */ -class lmdb::cursor { -protected: - MDB_cursor* _handle{nullptr}; - -public: - static constexpr unsigned int default_flags = 0; - - /** - * Creates an LMDB cursor. - * - * @param txn the transaction handle - * @param dbi the database handle - * @throws lmdb::error on failure - */ - static cursor - open(MDB_txn* const txn, - const MDB_dbi dbi) { - MDB_cursor* handle{}; - lmdb::cursor_open(txn, dbi, &handle); -#ifdef LMDBXX_DEBUG - assert(handle != nullptr); -#endif - return cursor{handle}; - } - - /** - * Constructor. - * - * @param handle a valid `MDB_cursor*` handle - */ - cursor(MDB_cursor* const handle) noexcept - : _handle{handle} {} - - /** - * Move constructor. - */ - cursor(cursor&& other) noexcept { - std::swap(_handle, other._handle); - } - - /** - * Move assignment operator. - */ - cursor& operator=(cursor&& other) noexcept { - if (this != &other) { - std::swap(_handle, other._handle); - } - return *this; - } - - /** - * Destructor. - */ - ~cursor() noexcept { - try { close(); } catch (...) {} - } - - /** - * Returns the underlying `MDB_cursor*` handle. - */ - operator MDB_cursor*() const noexcept { - return _handle; - } - - /** - * Returns the underlying `MDB_cursor*` handle. - */ - MDB_cursor* handle() const noexcept { - return _handle; - } - - /** - * Closes this cursor. - * - * @note this method is idempotent - * @post `handle() == nullptr` - */ - void close() noexcept { - if (_handle) { - lmdb::cursor_close(_handle); - _handle = nullptr; - } - } - - /** - * Renews this cursor. - * - * @param txn the transaction scope - * @throws lmdb::error on failure - */ - void renew(MDB_txn* const txn) { - lmdb::cursor_renew(txn, handle()); - } - - /** - * Returns the cursor's transaction handle. - */ - MDB_txn* txn() const noexcept { - return lmdb::cursor_txn(handle()); - } - - /** - * Returns the cursor's database handle. - */ - MDB_dbi dbi() const noexcept { - return lmdb::cursor_dbi(handle()); - } - - /** - * Retrieves a key from the database. - * - * @param key - * @param op - * @throws lmdb::error on failure - */ - bool get(MDB_val* const key, - const MDB_cursor_op op) { - return get(key, nullptr, op); - } - - /** - * Retrieves a key from the database. - * - * @param key - * @param op - * @throws lmdb::error on failure - */ - bool get(lmdb::val& key, - const MDB_cursor_op op) { - return get(key, nullptr, op); - } - - /** - * Retrieves a key/value pair from the database. - * - * @param key - * @param val (may be `nullptr`) - * @param op - * @throws lmdb::error on failure - */ - bool get(MDB_val* const key, - MDB_val* const val, - const MDB_cursor_op op) { - return lmdb::cursor_get(handle(), key, val, op); - } - - /** - * Retrieves a key/value pair from the database. - * - * @param key - * @param val - * @param op - * @throws lmdb::error on failure - */ - bool get(lmdb::val& key, - lmdb::val& val, - const MDB_cursor_op op) { - return lmdb::cursor_get(handle(), key, val, op); - } - - /** - * Retrieves a key/value pair from the database. - * - * @param key - * @param val - * @param op - * @throws lmdb::error on failure - */ - bool get(std::string& key, - std::string& val, - const MDB_cursor_op op) { - lmdb::val k{}, v{}; - const bool found = get(k, v, op); - if (found) { - key.assign(k.data(), k.size()); - val.assign(v.data(), v.size()); - } - return found; - } - - /** - * Positions this cursor at the given key. - * - * @param key - * @param op - * @throws lmdb::error on failure - */ - template - bool find(const K& key, - const MDB_cursor_op op = MDB_SET) { - lmdb::val k{&key, sizeof(K)}; - return get(k, nullptr, op); - } -}; - -//////////////////////////////////////////////////////////////////////////////// - -#endif /* LMDBXX_H */ diff --git a/main.cpp b/main.cpp index b37a0a0..fa3279b 100644 --- a/main.cpp +++ b/main.cpp @@ -1,10 +1,11 @@ #define CROW_ENABLE_SSL -#include "ext/crow/crow.h" +#include "src/page.h" + +#include "ext/crow/crow.h" #include "src/CmdLineOptions.h" #include "src/MicroCore.h" -#include "src/page.h" #include #include @@ -590,12 +591,24 @@ main(int ac, const char* av[]) if (enable_emission_monitor == true) { // finish Emission monitoring thread in a cotrolled manner. + + cout << "Waiting for emission monitoring thread to finish." << endl; + xmreg::CurrentBlockchainStatus::m_thread.interrupt(); xmreg::CurrentBlockchainStatus::m_thread.join(); - cout << "Emission monitoring thread joined." << endl; + cout << "Emission monitoring thread finished." << endl; } + // finish mempool thread + + cout << "Waiting for mempool monitoring thread to finish." << endl; + + xmerg::MempoolStatus::m_thread.interrupt(); + xmerg::MempoolStatus::m_thread.join(); + + cout << "Mmempool monitoring thread finished." << endl; + cout << "The explorer is terminating." << endl; return EXIT_SUCCESS; diff --git a/src/tools.h b/src/tools.h index df92449..ba63050 100644 --- a/src/tools.h +++ b/src/tools.h @@ -13,25 +13,29 @@ #define REMOVE_HASH_BRAKETS(a_hash) \ a_hash.substr(1, a_hash.size()-2) +#include "../ext/json.hpp" + #include "monero_headers.h" -#include "../ext/infix_iterator.h" #include "../ext/fmt/ostream.h" #include "../ext/fmt/format.h" -#include "../ext/json.hpp" + #include #include #include -#include +//#include #include #include -#include +//#include #include #include + + + /** * Some helper functions used in the example. * Names are rather self-explanatory, so I think @@ -216,21 +220,6 @@ namespace xmreg read(string filename); - -/** - * prints an iterable such as vector - */ - template - void print_iterable(const T & elems) { - - infix_ostream_iterator - oiter(std::cout, ","); - - std::cout << "["; - std::copy(elems.begin(), elems.end(),oiter); - std::cout << "]" << std::endl; - } - pair timestamps_time_scale(const vector& timestamps, uint64_t timeN, uint64_t resolution = 80,