diff --git a/source/dataman/CMakeLists.txt b/source/dataman/CMakeLists.txt
index f8ee0813ee7226d0632cc7cab9403b57ffeff2b1..5adafab771f64ee9ff140fea4a9bdaaa830f4f21 100644
--- a/source/dataman/CMakeLists.txt
+++ b/source/dataman/CMakeLists.txt
@@ -11,7 +11,10 @@ add_library(dataman
CacheMan.cpp CacheMan.h
)
target_include_directories(dataman PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
-target_link_libraries(dataman PRIVATE adios2sys)
+target_link_libraries(dataman
+ PRIVATE adios2sys
+ PUBLIC NLohmannJson
+)
list(APPEND dataman_targets dataman)
# Add the dataman plugins as MODULE libraries instead of SHARED libraries.
diff --git a/source/dataman/json.hpp b/source/dataman/json.hpp
deleted file mode 100644
index c695ce2156e2595ea40ca2e5528c11ff9dcdf64a..0000000000000000000000000000000000000000
--- a/source/dataman/json.hpp
+++ /dev/null
@@ -1,14554 +0,0 @@
-/*
- __ _____ _____ _____
- __| | __| | | | JSON for Modern C++
-| | |__ | | | | | | version 2.1.1
-|_____|_____|_____|_|___| https://github.com/nlohmann/json
-
-Licensed under the MIT License <http://opensource.org/licenses/MIT>.
-Copyright (c) 2013-2017 Niels Lohmann <http://nlohmann.me>.
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
-*/
-
-#ifndef NLOHMANN_JSON_HPP
-#define NLOHMANN_JSON_HPP
-
-#include <algorithm> // all_of, copy, fill, find, for_each, none_of, remove, reverse, transform
-#include <array> // array
-#include <cassert> // assert
-#include <ciso646> // and, not, or
-#include <clocale> // lconv, localeconv
-#include <cmath> // isfinite, labs, ldexp, signbit
-#include <cstddef> // nullptr_t, ptrdiff_t, size_t
-#include <cstdint> // int64_t, uint64_t
-#include <cstdlib> // abort, strtod, strtof, strtold, strtoul, strtoll, strtoull
-#include <cstring> // strlen
-#include <forward_list> // forward_list
-#include <functional> // function, hash, less
-#include <initializer_list> // initializer_list
-#include <iostream> // istream, ostream
-#include <iterator> // advance, begin, back_inserter, bidirectional_iterator_tag, distance, end, inserter, iterator, iterator_traits, next, random_access_iterator_tag, reverse_iterator
-#include <limits> // numeric_limits
-#include <locale> // locale
-#include <map> // map
-#include <memory> // addressof, allocator, allocator_traits, unique_ptr
-#include <numeric> // accumulate
-#include <sstream> // stringstream
-#include <string> // getline, stoi, string, to_string
-#include <type_traits> // 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 <utility> // declval, forward, make_pair, move, pair, swap
-#include <vector> // vector
-
-// exclude unsupported compilers
-#if defined(__clang__)
-#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__)
-#if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) < 40805
-#error \
- "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers"
-#endif
-#endif
-
-// disable float-equal warnings on GCC/clang
-#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
-#pragma GCC diagnostic push
-#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))
-#elif defined(_MSC_VER)
-#define JSON_DEPRECATED __declspec(deprecated)
-#else
-#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
-
-/*!
-@brief namespace for Niels Lohmann
-@see https://github.com/nlohmann
-@since version 1.0.0
-*/
-namespace nlohmann
-{
-
-/*!
-@brief unnamed namespace with internal helper functions
-
-This namespace collects some functions that could not be defined inside the
-@ref basic_json class.
-
-@since version 2.1.0
-*/
-namespace detail
-{
-////////////////
-// exceptions //
-////////////////
-
-/*!
-@brief general exception of the @ref basic_json class
-
-Extension of std::exception objects with a member @a id for exception ids.
-
-@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
-*/
-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:
- /// an exception object as storage for error messages
- std::runtime_error m;
-};
-
-/*!
-@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:
- /*!
- @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 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());
- }
-
-private:
- invalid_iterator(int id_, const char *what_arg) : exception(id_, what_arg)
- {
- }
-};
-
-/*!
-@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());
- }
-
-private:
- type_error(int id_, const char *what_arg) : exception(id_, what_arg) {}
-};
-
-/*!
-@brief exception indicating access out of the defined range
-
-Exceptions have ids 4xx.
-
-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.
-
-@since version 3.0.0
-*/
-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:
- out_of_range(int id_, const char *what_arg) : exception(id_, what_arg) {}
-};
-
-/*!
-@brief exception indicating other errors
-
-Exceptions have ids 5xx.
-
-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.
-
-@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());
- }
-
-private:
- other_error(int id_, const char *what_arg) : exception(id_, what_arg) {}
-};
-
-///////////////////////////
-// JSON type enumeration //
-///////////////////////////
-
-/*!
-@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
-
-@since version 1.0.0
-*/
-inline bool operator<(const value_t lhs, const value_t rhs) noexcept
-{
- static constexpr std::array<uint8_t, 8> 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 false;
- }
-
- return order[static_cast<std::size_t>(lhs)] <
- order[static_cast<std::size_t>(rhs)];
-}
-
-/////////////
-// helpers //
-/////////////
-
-// alias templates to reduce boilerplate
-template <bool B, typename T = void>
-using enable_if_t = typename std::enable_if<B, T>::type;
-
-template <typename T>
-using uncvref_t =
- typename std::remove_cv<typename std::remove_reference<T>::type>::type;
-
-/*
-Implementation of two C++17 constructs: conjunction, negation. This is needed
-to avoid evaluating all the traits in a condition
-
-For example: not std::is_same<void, T>::value and has_value_type<T>::value
-will not compile when T = void (on MSVC at least). Whereas
-conjunction<negation<std::is_same<void, T>>, has_value_type<T>>::value will
-stop evaluating if negation<...>::value == false
-
-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 <class...>
-struct conjunction : std::true_type
-{
-};
-template <class B1>
-struct conjunction<B1> : B1
-{
-};
-template <class B1, class... Bn>
-struct conjunction<B1, Bn...>
- : std::conditional<bool(B1::value), conjunction<Bn...>, B1>::type
-{
-};
-
-template <class B>
-struct negation : std::integral_constant<bool, !B::value>
-{
-};
-
-// dispatch utility (taken from ranges-v3)
-template <unsigned N>
-struct priority_tag : priority_tag<N - 1>
-{
-};
-template <>
-struct priority_tag<0>
-{
-};
-
-//////////////////
-// constructors //
-//////////////////
-
-template <value_t>
-struct external_constructor;
-
-template <>
-struct external_constructor<value_t::boolean>
-{
- template <typename BasicJsonType>
- static void construct(BasicJsonType &j,
- typename BasicJsonType::boolean_t b) noexcept
- {
- j.m_type = value_t::boolean;
- j.m_value = b;
- j.assert_invariant();
- }
-};
-
-template <>
-struct external_constructor<value_t::string>
-{
- template <typename BasicJsonType>
- static void construct(BasicJsonType &j,
- const typename BasicJsonType::string_t &s)
- {
- j.m_type = value_t::string;
- j.m_value = s;
- j.assert_invariant();
- }
-};
-
-template <>
-struct external_constructor<value_t::number_float>
-{
- template <typename BasicJsonType>
- 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();
- }
-};
-
-template <>
-struct external_constructor<value_t::number_unsigned>
-{
- template <typename BasicJsonType>
- 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();
- }
-};
-
-template <>
-struct external_constructor<value_t::number_integer>
-{
- template <typename BasicJsonType>
- 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();
- }
-};
-
-template <>
-struct external_constructor<value_t::array>
-{
- template <typename BasicJsonType>
- static void construct(BasicJsonType &j,
- const typename BasicJsonType::array_t &arr)
- {
- j.m_type = value_t::array;
- j.m_value = arr;
- j.assert_invariant();
- }
-
- template <
- typename BasicJsonType, typename CompatibleArrayType,
- enable_if_t<not std::is_same<CompatibleArrayType,
- typename BasicJsonType::array_t>::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<typename BasicJsonType::array_t>(
- begin(arr), end(arr));
- j.assert_invariant();
- }
-
- template <typename BasicJsonType>
- static void construct(BasicJsonType &j, const std::vector<bool> &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();
- }
-};
-
-template <>
-struct external_constructor<value_t::object>
-{
- template <typename BasicJsonType>
- static void construct(BasicJsonType &j,
- const typename BasicJsonType::object_t &obj)
- {
- j.m_type = value_t::object;
- j.m_value = obj;
- j.assert_invariant();
- }
-
- template <
- typename BasicJsonType, typename CompatibleObjectType,
- enable_if_t<not std::is_same<CompatibleObjectType,
- typename BasicJsonType::object_t>::value,
- int> = 0>
- static void construct(BasicJsonType &j, const CompatibleObjectType &obj)
- {
- using std::begin;
- using std::end;
-
- j.m_type = value_t::object;
- j.m_value.object = j.template create<typename BasicJsonType::object_t>(
- begin(obj), end(obj));
- j.assert_invariant();
- }
-};
-
-////////////////////////
-// has_/is_ functions //
-////////////////////////
-
-/*!
-@brief Helper to determine whether there's a key_type for T.
-
-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.
-
-@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 <typename T> \
- struct has_##type \
- { \
- private: \
- template <typename U, typename = typename U::type> \
- static int detect(U &&); \
- static void detect(...); \
- \
- public: \
- static constexpr bool value = \
- std::is_integral<decltype(detect(std::declval<T>()))>::value; \
- }
-
-NLOHMANN_JSON_HAS_HELPER(mapped_type);
-NLOHMANN_JSON_HAS_HELPER(key_type);
-NLOHMANN_JSON_HAS_HELPER(value_type);
-NLOHMANN_JSON_HAS_HELPER(iterator);
-
-#undef NLOHMANN_JSON_HAS_HELPER
-
-template <bool B, class RealType, class CompatibleObjectType>
-struct is_compatible_object_type_impl : std::false_type
-{
-};
-
-template <class RealType, class CompatibleObjectType>
-struct is_compatible_object_type_impl<true, RealType, CompatibleObjectType>
-{
- static constexpr auto value =
- std::is_constructible<
- typename RealType::key_type,
- typename CompatibleObjectType::key_type>::value and
- std::is_constructible<
- typename RealType::mapped_type,
- typename CompatibleObjectType::mapped_type>::value;
-};
-
-template <class BasicJsonType, class CompatibleObjectType>
-struct is_compatible_object_type
-{
- static auto constexpr value = is_compatible_object_type_impl<
- conjunction<negation<std::is_same<void, CompatibleObjectType>>,
- has_mapped_type<CompatibleObjectType>,
- has_key_type<CompatibleObjectType>>::value,
- typename BasicJsonType::object_t, CompatibleObjectType>::value;
-};
-
-template <typename BasicJsonType, typename T>
-struct is_basic_json_nested_type
-{
- static auto constexpr value =
- std::is_same<T, typename BasicJsonType::iterator>::value or
- std::is_same<T, typename BasicJsonType::const_iterator>::value or
- std::is_same<T, typename BasicJsonType::reverse_iterator>::value or
- std::is_same<T,
- typename BasicJsonType::const_reverse_iterator>::value or
- std::is_same<T, typename BasicJsonType::json_pointer>::value;
-};
-
-template <class BasicJsonType, class CompatibleArrayType>
-struct is_compatible_array_type
-{
- static auto constexpr value = conjunction<
- negation<std::is_same<void, CompatibleArrayType>>,
- negation<is_compatible_object_type<BasicJsonType, CompatibleArrayType>>,
- negation<std::is_constructible<typename BasicJsonType::string_t,
- CompatibleArrayType>>,
- negation<is_basic_json_nested_type<BasicJsonType, CompatibleArrayType>>,
- has_value_type<CompatibleArrayType>,
- has_iterator<CompatibleArrayType>>::value;
-};
-
-template <bool, typename, typename>
-struct is_compatible_integer_type_impl : std::false_type
-{
-};
-
-template <typename RealIntegerType, typename CompatibleNumberIntegerType>
-struct is_compatible_integer_type_impl<true, RealIntegerType,
- CompatibleNumberIntegerType>
-{
- // is there an assert somewhere on overflows?
- using RealLimits = std::numeric_limits<RealIntegerType>;
- using CompatibleLimits = std::numeric_limits<CompatibleNumberIntegerType>;
-
- static constexpr auto value =
- std::is_constructible<RealIntegerType,
- CompatibleNumberIntegerType>::value and
- CompatibleLimits::is_integer and
- RealLimits::is_signed == CompatibleLimits::is_signed;
-};
-
-template <typename RealIntegerType, typename CompatibleNumberIntegerType>
-struct is_compatible_integer_type
-{
- static constexpr auto
- value = is_compatible_integer_type_impl <
- std::is_integral<CompatibleNumberIntegerType>::value and
- not std::is_same<bool, CompatibleNumberIntegerType>::value,
- RealIntegerType, CompatibleNumberIntegerType > ::value;
-};
-
-// trait checking if JSONSerializer<T>::from_json(json const&, udt&) exists
-template <typename BasicJsonType, typename T>
-struct has_from_json
-{
-private:
- // also check the return type of from_json
- template <typename U, typename = enable_if_t<std::is_same<
- void, decltype(uncvref_t<U>::from_json(
- std::declval<BasicJsonType>(),
- std::declval<T &>()))>::value>>
- static int detect(U &&);
- static void detect(...);
-
-public:
- static constexpr bool value = std::is_integral<decltype(
- detect(std::declval<typename BasicJsonType::template json_serializer<
- T, void>>()))>::value;
-};
-
-// This trait checks if JSONSerializer<T>::from_json(json const&) exists
-// this overload is used for non-default-constructible user-defined-types
-template <typename BasicJsonType, typename T>
-struct has_non_default_from_json
-{
-private:
- template <typename U, typename = enable_if_t<std::is_same<
- T, decltype(uncvref_t<U>::from_json(
- std::declval<BasicJsonType>()))>::value>>
- static int detect(U &&);
- static void detect(...);
-
-public:
- static constexpr bool value = std::is_integral<decltype(
- detect(std::declval<typename BasicJsonType::template json_serializer<
- T, void>>()))>::value;
-};
-
-// This trait checks if BasicJsonType::json_serializer<T>::to_json exists
-template <typename BasicJsonType, typename T>
-struct has_to_json
-{
-private:
- template <typename U,
- typename = decltype(uncvref_t<U>::to_json(
- std::declval<BasicJsonType &>(), std::declval<T>()))>
- static int detect(U &&);
- static void detect(...);
-
-public:
- static constexpr bool value = std::is_integral<decltype(
- detect(std::declval<typename BasicJsonType::template json_serializer<
- T, void>>()))>::value;
-};
-
-/////////////
-// to_json //
-/////////////
-
-template <typename BasicJsonType, typename T,
- enable_if_t<std::is_same<T, typename BasicJsonType::boolean_t>::value,
- int> = 0>
-void to_json(BasicJsonType &j, T b) noexcept
-{
- external_constructor<value_t::boolean>::construct(j, b);
-}
-
-template <typename BasicJsonType, typename CompatibleString,
- enable_if_t<std::is_constructible<typename BasicJsonType::string_t,
- CompatibleString>::value,
- int> = 0>
-void to_json(BasicJsonType &j, const CompatibleString &s)
-{
- external_constructor<value_t::string>::construct(j, s);
-}
-
-template <typename BasicJsonType, typename FloatType,
- enable_if_t<std::is_floating_point<FloatType>::value, int> = 0>
-void to_json(BasicJsonType &j, FloatType val) noexcept
-{
- external_constructor<value_t::number_float>::construct(
- j, static_cast<typename BasicJsonType::number_float_t>(val));
-}
-
-template <typename BasicJsonType, typename CompatibleNumberUnsignedType,
- enable_if_t<is_compatible_integer_type<
- typename BasicJsonType::number_unsigned_t,
- CompatibleNumberUnsignedType>::value,
- int> = 0>
-void to_json(BasicJsonType &j, CompatibleNumberUnsignedType val) noexcept
-{
- external_constructor<value_t::number_unsigned>::construct(
- j, static_cast<typename BasicJsonType::number_unsigned_t>(val));
-}
-
-template <typename BasicJsonType, typename CompatibleNumberIntegerType,
- enable_if_t<is_compatible_integer_type<
- typename BasicJsonType::number_integer_t,
- CompatibleNumberIntegerType>::value,
- int> = 0>
-void to_json(BasicJsonType &j, CompatibleNumberIntegerType val) noexcept
-{
- external_constructor<value_t::number_integer>::construct(
- j, static_cast<typename BasicJsonType::number_integer_t>(val));
-}
-
-template <typename BasicJsonType, typename EnumType,
- enable_if_t<std::is_enum<EnumType>::value, int> = 0>
-void to_json(BasicJsonType &j, EnumType e) noexcept
-{
- using underlying_type = typename std::underlying_type<EnumType>::type;
- external_constructor<value_t::number_integer>::construct(
- j, static_cast<underlying_type>(e));
-}
-
-template <typename BasicJsonType>
-void to_json(BasicJsonType &j, const std::vector<bool> &e)
-{
- external_constructor<value_t::array>::construct(j, e);
-}
-
-template <typename BasicJsonType, typename CompatibleArrayType,
- enable_if_t<is_compatible_array_type<BasicJsonType,
- CompatibleArrayType>::value or
- std::is_same<typename BasicJsonType::array_t,
- CompatibleArrayType>::value,
- int> = 0>
-void to_json(BasicJsonType &j, const CompatibleArrayType &arr)
-{
- external_constructor<value_t::array>::construct(j, arr);
-}
-
-template <typename BasicJsonType, typename CompatibleObjectType,
- enable_if_t<is_compatible_object_type<BasicJsonType,
- CompatibleObjectType>::value,
- int> = 0>
-void to_json(BasicJsonType &j, const CompatibleObjectType &arr)
-{
- external_constructor<value_t::object>::construct(j, arr);
-}
-
-template <typename BasicJsonType, typename T, std::size_t N,
- enable_if_t<not std::is_constructible<
- typename BasicJsonType::string_t, T (&)[N]>::value,
- int> = 0>
-void to_json(BasicJsonType &j, T (&arr)[N])
-{
- external_constructor<value_t::array>::construct(j, arr);
-}
-
-///////////////
-// from_json //
-///////////////
-
-// overloads for basic_json template parameters
-template <
- typename BasicJsonType, typename ArithmeticType,
- enable_if_t<std::is_arithmetic<ArithmeticType>::value and
- not std::is_same<ArithmeticType,
- typename BasicJsonType::boolean_t>::value,
- int> = 0>
-void get_arithmetic_value(const BasicJsonType &j, ArithmeticType &val)
-{
- switch (static_cast<value_t>(j))
- {
- case value_t::number_unsigned:
- {
- val = static_cast<ArithmeticType>(
- *j.template get_ptr<
- const typename BasicJsonType::number_unsigned_t *>());
- break;
- }
- case value_t::number_integer:
- {
- val = static_cast<ArithmeticType>(
- *j.template get_ptr<
- const typename BasicJsonType::number_integer_t *>());
- break;
- }
- case value_t::number_float:
- {
- val = static_cast<ArithmeticType>(
- *j.template get_ptr<
- const typename BasicJsonType::number_float_t *>());
- break;
- }
- default:
- {
- JSON_THROW(type_error::create(302, "type must be number, but is " +
- j.type_name()));
- }
- }
-}
-
-template <typename BasicJsonType>
-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<const typename BasicJsonType::boolean_t *>();
-}
-
-template <typename BasicJsonType>
-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<const typename BasicJsonType::string_t *>();
-}
-
-template <typename BasicJsonType>
-void from_json(const BasicJsonType &j,
- typename BasicJsonType::number_float_t &val)
-{
- get_arithmetic_value(j, val);
-}
-
-template <typename BasicJsonType>
-void from_json(const BasicJsonType &j,
- typename BasicJsonType::number_unsigned_t &val)
-{
- get_arithmetic_value(j, val);
-}
-
-template <typename BasicJsonType>
-void from_json(const BasicJsonType &j,
- typename BasicJsonType::number_integer_t &val)
-{
- get_arithmetic_value(j, val);
-}
-
-template <typename BasicJsonType, typename EnumType,
- enable_if_t<std::is_enum<EnumType>::value, int> = 0>
-void from_json(const BasicJsonType &j, EnumType &e)
-{
- typename std::underlying_type<EnumType>::type val;
- get_arithmetic_value(j, val);
- e = static_cast<EnumType>(val);
-}
-
-template <typename BasicJsonType>
-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<const typename BasicJsonType::array_t *>();
-}
-
-// forward_list doesn't have an insert method
-template <typename BasicJsonType, typename T, typename Allocator,
- enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
-void from_json(const BasicJsonType &j, std::forward_list<T, Allocator> &l)
-{
- if (not j.is_array())
- {
- JSON_THROW(type_error::create(302, "type must be array, but is " +
- j.type_name()));
- }
-
- for (auto it = j.rbegin(), end = j.rend(); it != end; ++it)
- {
- l.push_front(it->template get<T>());
- }
-}
-
-template <typename BasicJsonType, typename CompatibleArrayType>
-void from_json_array_impl(const BasicJsonType &j, CompatibleArrayType &arr,
- priority_tag<0>)
-{
- using std::begin;
- using std::end;
-
- std::transform(
- j.begin(), j.end(), std::inserter(arr, end(arr)),
- [](const BasicJsonType &i) {
- // get<BasicJsonType>() returns *this, this won't call a from_json
- // method when value_type is BasicJsonType
- return i.template get<typename CompatibleArrayType::value_type>();
- });
-}
-
-template <typename BasicJsonType, typename CompatibleArrayType>
-auto from_json_array_impl(const BasicJsonType &j, CompatibleArrayType &arr,
- priority_tag<1>)
- -> decltype(
- arr.reserve(std::declval<typename CompatibleArrayType::size_type>()),
- void())
-{
- using std::begin;
- using std::end;
-
- arr.reserve(j.size());
- std::transform(
- j.begin(), j.end(), std::inserter(arr, end(arr)),
- [](const BasicJsonType &i) {
- // get<BasicJsonType>() returns *this, this won't call a from_json
- // method when value_type is BasicJsonType
- return i.template get<typename CompatibleArrayType::value_type>();
- });
-}
-
-template <
- typename BasicJsonType, typename CompatibleArrayType,
- enable_if_t<
- is_compatible_array_type<BasicJsonType, CompatibleArrayType>::value and
- std::is_convertible<BasicJsonType, typename CompatibleArrayType::
- value_type>::value and
- not std::is_same<typename BasicJsonType::array_t,
- CompatibleArrayType>::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()));
- }
-
- from_json_array_impl(j, arr, priority_tag<1>{});
-}
-
-template <typename BasicJsonType, typename CompatibleObjectType,
- enable_if_t<is_compatible_object_type<BasicJsonType,
- CompatibleObjectType>::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()));
- }
-
- auto inner_object =
- j.template get_ptr<const typename BasicJsonType::object_t *>();
- 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));
-}
-
-// 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 <
- typename BasicJsonType, typename ArithmeticType,
- enable_if_t<
- std::is_arithmetic<ArithmeticType>::value and
- not std::is_same<ArithmeticType, typename BasicJsonType::
- number_unsigned_t>::value and
- not std::is_same<ArithmeticType, typename BasicJsonType::
- number_integer_t>::value and
- not std::is_same<ArithmeticType,
- typename BasicJsonType::number_float_t>::value and
- not std::is_same<ArithmeticType,
- typename BasicJsonType::boolean_t>::value,
- int> = 0>
-void from_json(const BasicJsonType &j, ArithmeticType &val)
-{
- switch (static_cast<value_t>(j))
- {
- case value_t::number_unsigned:
- {
- val = static_cast<ArithmeticType>(
- *j.template get_ptr<
- const typename BasicJsonType::number_unsigned_t *>());
- break;
- }
- case value_t::number_integer:
- {
- val = static_cast<ArithmeticType>(
- *j.template get_ptr<
- const typename BasicJsonType::number_integer_t *>());
- break;
- }
- case value_t::number_float:
- {
- val = static_cast<ArithmeticType>(
- *j.template get_ptr<
- const typename BasicJsonType::number_float_t *>());
- break;
- }
- case value_t::boolean:
- {
- val = static_cast<ArithmeticType>(
- *j.template get_ptr<const typename BasicJsonType::boolean_t *>());
- break;
- }
- default:
- {
- JSON_THROW(type_error::create(302, "type must be number, but is " +
- j.type_name()));
- }
- }
-}
-
-struct to_json_fn
-{
-private:
- template <typename BasicJsonType, typename T>
- auto call(BasicJsonType &j, T &&val, priority_tag<1>) const
- noexcept(noexcept(to_json(j, std::forward<T>(val))))
- -> decltype(to_json(j, std::forward<T>(val)), void())
- {
- return to_json(j, std::forward<T>(val));
- }
-
- template <typename BasicJsonType, typename T>
- void call(BasicJsonType &, T &&, priority_tag<0>) const noexcept
- {
- static_assert(sizeof(BasicJsonType) == 0,
- "could not find to_json() method in T's namespace");
- }
-
-public:
- template <typename BasicJsonType, typename T>
- void operator()(BasicJsonType &j, T &&val) const
- noexcept(noexcept(std::declval<to_json_fn>().call(j,
- std::forward<T>(val),
- priority_tag<1>{})))
- {
- return call(j, std::forward<T>(val), priority_tag<1>{});
- }
-};
-
-struct from_json_fn
-{
-private:
- template <typename BasicJsonType, typename T>
- 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);
- }
-
- template <typename BasicJsonType, typename T>
- 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");
- }
-
-public:
- template <typename BasicJsonType, typename T>
- void operator()(const BasicJsonType &j, T &val) const
- noexcept(noexcept(std::declval<from_json_fn>().call(j, val,
- priority_tag<1>{})))
- {
- return call(j, val, priority_tag<1>{});
- }
-};
-
-// taken from ranges-v3
-template <typename T>
-struct static_const
-{
- static constexpr T value{};
-};
-
-template <typename T>
-constexpr T static_const<T>::value;
-} // namespace detail
-
-/// namespace to hold default `to_json` / `from_json` functions
-namespace
-{
-constexpr const auto &to_json = detail::static_const<detail::to_json_fn>::value;
-constexpr const auto &from_json =
- detail::static_const<detail::from_json_fn>::value;
-}
-
-/*!
-@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 <typename = void, typename = void>
-struct adl_serializer
-{
- /*!
- @brief convert a JSON value to any value type
-
- This function is usually called by the `get()` function of the
- @ref basic_json class (either explicit or via conversion operators).
-
- @param[in] j JSON value to read from
- @param[in,out] val value to write to
- */
- template <typename BasicJsonType, typename ValueType>
- static void from_json(BasicJsonType &&j, ValueType &val) noexcept(
- noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val)))
- {
- ::nlohmann::from_json(std::forward<BasicJsonType>(j), val);
- }
-
- /*!
- @brief convert any value type to a JSON value
-
- This function is usually called by the constructors of the @ref basic_json
- class.
-
- @param[in,out] j JSON value to write to
- @param[in] val value to read from
- */
- template <typename BasicJsonType, typename ValueType>
- static void to_json(BasicJsonType &j, ValueType &&val) noexcept(
- noexcept(::nlohmann::to_json(j, std::forward<ValueType>(val))))
- {
- ::nlohmann::to_json(j, std::forward<ValueType>(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 <typename U, typename V, typename... Args> class ObjectType =
- std::map,
- template <typename U, typename... Args> 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 <typename U> class AllocatorType = std::allocator,
- template <typename T, typename SFINAE = void> class JSONSerializer =
- adl_serializer>
-class basic_json
-{
-private:
- template <detail::value_t>
- friend struct detail::external_constructor;
- /// workaround type for MSVC
- using basic_json_t =
- basic_json<ObjectType, ArrayType, StringType, BooleanType,
- NumberIntegerType, NumberUnsignedType, NumberFloatType,
- AllocatorType, JSONSerializer>;
-
-public:
- using value_t = detail::value_t;
- // forward declarations
- template <typename U>
- class iter_impl;
- template <typename Base>
- class json_reverse_iterator;
- class json_pointer;
- template <typename T, typename SFINAE>
- using json_serializer = JSONSerializer<T, SFINAE>;
-
- ////////////////
- // 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<basic_json>;
-
- /// the type of an element pointer
- using pointer = typename std::allocator_traits<allocator_type>::pointer;
- /// the type of an element const pointer
- using const_pointer =
- typename std::allocator_traits<allocator_type>::const_pointer;
-
- /// an iterator for a basic_json container
- using iterator = iter_impl<basic_json>;
- /// a const iterator for a basic_json container
- using const_iterator = iter_impl<const basic_json>;
- /// a reverse iterator for a basic_json container
- using reverse_iterator =
- json_reverse_iterator<typename basic_json::iterator>;
- /// a const reverse iterator for a basic_json container
- using const_reverse_iterator =
- json_reverse_iterator<typename basic_json::const_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 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<StringType>` 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<std::string>, // key_compare
- std::allocator<std::pair<const std::string, basic_json>> // 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<StringType, basic_json, std::less<StringType>,
- AllocatorType<std::pair<const StringType, basic_json>>>;
-
- /*!
- @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<basic_json> // 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<basic_json, AllocatorType<basic_json>>;
-
- /*!
- @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 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
-
- [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
-
- 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 number_unsigned_t -- type for number values (unsigned integer)
-
- @since version 1.0.0
- */
- using number_float_t = NumberFloatType;
-
- /// @}
-
-private:
- /// helper for exception-safe object creation
- template <typename T, typename... Args>
- static T *create(Args &&... args)
- {
- AllocatorType<T> alloc;
- auto deleter = [&](T *object) { alloc.deallocate(object, 1); };
- std::unique_ptr<T, decltype(deleter)> object(alloc.allocate(1),
- deleter);
- alloc.construct(object.get(), std::forward<Args>(args)...);
- assert(object != nullptr);
- return object.release();
- }
-
- ////////////////////////
- // JSON value storage //
- ////////////////////////
-
- /*!
- @brief a JSON value
-
- The actual storage for a JSON value of the @ref basic_json class. This
- union combines the different storage types for the JSON value types
- defined in @ref value_t.
-
- JSON type | value_t type | used type
- --------- | --------------- | ------------------------
- object | object | pointer to @ref object_t
- array | array | pointer to @ref array_t
- string | string | pointer to @ref string_t
- boolean | boolean | @ref boolean_t
- number | number_integer | @ref number_integer_t
- number | number_unsigned | @ref number_unsigned_t
- number | number_float | @ref number_float_t
- null | null | *no value is stored*
-
- @note Variable-length types (objects, arrays, and strings) are stored as
- pointers. The size of the union should not exceed 64 bits if the default
- value types are used.
-
- @since version 1.0.0
- */
- union json_value {
- /// object (stored with pointer to save storage)
- object_t *object;
- /// array (stored with pointer to save storage)
- array_t *array;
- /// string (stored with pointer to save storage)
- string_t *string;
- /// boolean
- boolean_t boolean;
- /// number (integer)
- number_integer_t number_integer;
- /// number (unsigned integer)
- number_unsigned_t number_unsigned;
- /// number (floating-point)
- number_float_t number_float;
-
- /// default constructor (for null values)
- json_value() = default;
- /// constructor for booleans
- json_value(boolean_t v) noexcept : boolean(v) {}
- /// constructor for numbers (integer)
- json_value(number_integer_t v) noexcept : number_integer(v) {}
- /// constructor for numbers (unsigned)
- json_value(number_unsigned_t v) noexcept : number_unsigned(v) {}
- /// constructor for numbers (floating-point)
- json_value(number_float_t v) noexcept : number_float(v) {}
- /// constructor for empty values of a given type
- json_value(value_t t)
- {
- switch (t)
- {
- case value_t::object:
- {
- object = create<object_t>();
- break;
- }
-
- case value_t::array:
- {
- array = create<array_t>();
- break;
- }
-
- case value_t::string:
- {
- string = create<string_t>("");
- break;
- }
-
- case value_t::boolean:
- {
- boolean = boolean_t(false);
- break;
- }
-
- case value_t::number_integer:
- {
- number_integer = number_integer_t(0);
- break;
- }
-
- case value_t::number_unsigned:
- {
- number_unsigned = number_unsigned_t(0);
- break;
- }
-
- case value_t::number_float:
- {
- number_float = number_float_t(0.0);
- break;
- }
-
- case value_t::null:
- {
- break;
- }
-
- default:
- {
- if (t == value_t::null)
- {
- JSON_THROW(
- other_error::create(500,
- "961c151d2e87f2686a955a9be24d316f13"
- "62bf21 2.1.1")); // LCOV_EXCL_LINE
- }
- break;
- }
- }
- }
-
- /// constructor for strings
- json_value(const string_t &value) { string = create<string_t>(value); }
-
- /// constructor for objects
- json_value(const object_t &value) { object = create<object_t>(value); }
-
- /// constructor for arrays
- json_value(const array_t &value) { array = create<array_t>(value); }
- };
-
- /*!
- @brief checks the class invariants
-
- This function asserts the class invariants. It needs to be called at the
- end of every constructor to make sure that created objects respect the
- invariant. Furthermore, it has to be called each time the type of a JSON
- value is changed, because the invariant expresses a relationship between
- @a m_type and @a m_value.
- */
- void assert_invariant() const
- {
- assert(m_type != value_t::object or m_value.object != nullptr);
- assert(m_type != value_t::array or m_value.array != nullptr);
- assert(m_type != value_t::string or m_value.string != nullptr);
- }
-
-public:
- //////////////////////////
- // JSON parser callback //
- //////////////////////////
-
- /*!
- @brief JSON callback events
-
- This enumeration lists the parser events that can trigger calling a
- callback function of type @ref parser_callback_t during parsing.
-
- @image html callback_events.png "Example when certain parse events are
- triggered"
-
- @since version 1.0.0
- */
- enum class parse_event_t : uint8_t
- {
- /// the parser read `{` and started to process a JSON object
- object_start,
- /// the parser read `}` and finished processing a JSON object
- object_end,
- /// the parser read `[` and started to process a JSON array
- array_start,
- /// the parser read `]` and finished processing a JSON array
- array_end,
- /// the parser read a key of a value in an object
- key,
- /// the parser finished reading a JSON value
- value
- };
-
- /*!
- @brief per-element parser callback type
-
- 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 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
- indicating whether the element that emitted the callback shall be kept or
- not.
-
- We distinguish six scenarios (determined by the event type) in which the
- callback function can be called. The following table describes the values
- of the parameters @a depth, @a event, and @a parsed.
-
- parameter @a event | description | parameter @a depth | parameter @a parsed
- ------------------ | ----------- | ------------------ | -------------------
- parse_event_t::object_start | the parser read `{` and started to process a
- JSON object | depth of the parent of the JSON object | a JSON value with
- type discarded
- parse_event_t::key | the parser read a key of a value in an object | depth
- of the currently parsed JSON object | a JSON string containing the key
- parse_event_t::object_end | the parser read `}` and finished processing a
- JSON object | depth of the parent of the JSON object | the parsed JSON
- object
- parse_event_t::array_start | the parser read `[` and started to process a
- JSON array | depth of the parent of the JSON array | a JSON value with type
- discarded
- parse_event_t::array_end | the parser read `]` and finished processing a
- JSON array | depth of the parent of the JSON array | the parsed JSON array
- parse_event_t::value | the parser finished reading a JSON value | depth of
- the value | the parsed JSON value
-
- @image html callback_events.png "Example when certain parse events are
- triggered"
-
- Discarding a value (i.e., returning `false`) has different effects
- depending on the context in which function was called:
-
- - Discarded values in structured types are skipped. That is, the parser
- will behave as if the discarded value was never read.
- - In case a value outside a structured type is skipped, it is replaced
- with `null`. This case happens if the top-level element is skipped.
-
- @param[in] depth the depth of the recursion during parsing
-
- @param[in] event an event of type parse_event_t indicating the context in
- the callback function has been called
-
- @param[in,out] parsed the current intermediate parse result; note that
- writing to this value has no effect for parse_event_t::key events
-
- @return Whether the JSON value which called the function during parsing
- should be kept (`true`) or not (`false`). In the latter case, it is either
- skipped completely or replaced by an empty discarded object.
-
- @sa @ref parse(std::istream&, parser_callback_t) or
- @ref parse(const CharT, const parser_callback_t) for examples
-
- @since version 1.0.0
- */
- using parser_callback_t =
- std::function<bool(int depth, parse_event_t event, basic_json &parsed)>;
-
- //////////////////
- // constructors //
- //////////////////
-
- /// @name constructors and destructors
- /// Constructors of class @ref basic_json, copy/move constructor, copy
- /// assignment, static functions creating objects, and the destructor.
- /// @{
-
- /*!
- @brief create an empty value with a given type
-
- Create an empty JSON value with a given type. The value will be default
- initialized with an empty value which depends on the type:
-
- Value type | initial value
- ----------- | -------------
- null | `null`
- boolean | `false`
- string | `""`
- number | `0`
- object | `{}`
- array | `[]`
-
- @param[in] value_type the type of the value to create
-
- @complexity Constant.
-
- @liveexample{The following code shows the constructor for different @ref
- value_t values,basic_json__value_t}
-
- @since version 1.0.0
- */
- basic_json(const value_t value_type)
- : m_type(value_type), m_value(value_type)
- {
- assert_invariant();
- }
-
- /*!
- @brief create a null object
-
- Create a `null` JSON value. It either takes a null pointer as parameter
- (explicitly creating `null`) or no parameter (implicitly creating `null`).
- The passed null pointer itself is not read -- it is only used to choose
- the right constructor.
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this constructor never throws
- exceptions.
-
- @liveexample{The following code shows the constructor with and without a
- null pointer parameter.,basic_json__nullptr_t}
-
- @since version 1.0.0
- */
- basic_json(std::nullptr_t = nullptr) noexcept : basic_json(value_t::null)
- {
- assert_invariant();
- }
-
- /*!
- @brief create a JSON value
-
- 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<U>::to_json` method
- with `U = uncvref_t<CompatibleType>`, to be exact).
-
- 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.
-
- See the examples below.
-
- @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<U> has a
- `to_json(basic_json_t&, CompatibleType&&)` method
-
- @tparam U = `uncvref_t<CompatibleType>`
-
- @param[in] val the value to be forwarded
-
- @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<U>::to_json()` throws
-
- @liveexample{The following code shows the constructor with several
- compatible types.,basic_json__CompatibleType}
-
- @since version 2.1.0
- */
- template <
- typename CompatibleType, typename U = detail::uncvref_t<CompatibleType>,
- detail::enable_if_t<not std::is_base_of<std::istream, U>::value and
- not std::is_same<U, basic_json_t>::value and
- not detail::is_basic_json_nested_type<
- basic_json_t, U>::value and
- detail::has_to_json<basic_json, U>::value,
- int> = 0>
- basic_json(CompatibleType &&val) noexcept(
- noexcept(JSONSerializer<U>::to_json(std::declval<basic_json_t &>(),
- std::forward<CompatibleType>(val))))
- {
- JSONSerializer<U>::to_json(*this, std::forward<CompatibleType>(val));
- assert_invariant();
- }
-
- /*!
- @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<basic_json>)
- with an empty initializer list in this case
- - arrays whose elements satisfy rule 2: use @ref
- array(std::initializer_list<basic_json>) 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
-
- @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<basic_json>) and
- @ref object(std::initializer_list<basic_json>).
-
- @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
-
- @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<basic_json>)
- for an example.
-
- @complexity Linear in the size of the initializer list @a init.
-
- @liveexample{The example below shows how JSON values are created from
- initializer lists.,basic_json__list_init_t}
-
- @sa @ref array(std::initializer_list<basic_json>) -- create a JSON array
- value from an initializer list
- @sa @ref object(std::initializer_list<basic_json>) -- create a JSON object
- value from an initializer list
-
- @since version 1.0.0
- */
- basic_json(std::initializer_list<basic_json> init,
- bool type_deduction = true, value_t manual_type = value_t::array)
- {
- // 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<array_t>(init);
- }
-
- assert_invariant();
- }
-
- /*!
- @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.
-
- @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<basic_json>, 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] init initializer list with JSON values to create an array from
- (optional)
-
- @return JSON array value
-
- @complexity Linear in the size of @a init.
-
- @liveexample{The following code shows an example for the `array`
- function.,array}
-
- @sa @ref basic_json(std::initializer_list<basic_json>, bool, value_t) --
- create a JSON value from an initializer list
- @sa @ref object(std::initializer_list<basic_json>) -- create a JSON object
- value from an initializer list
-
- @since version 1.0.0
- */
- static basic_json array(std::initializer_list<basic_json> init =
- std::initializer_list<basic_json>())
- {
- return basic_json(init, false, value_t::array);
- }
-
- /*!
- @brief explicitly create an object from an initializer list
-
- 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<basic_json>), 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<basic_json>, bool,
- value_t).
-
- @param[in] init initializer list to create an object from (optional)
-
- @return JSON object value
-
- @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<basic_json>, bool,
- value_t),
- an array would have been created from the passed initializer list @a init.
- See example below.
-
- @complexity Linear in the size of @a init.
-
- @liveexample{The following code shows an example for the `object`
- function.,object}
-
- @sa @ref basic_json(std::initializer_list<basic_json>, bool, value_t) --
- create a JSON value from an initializer list
- @sa @ref array(std::initializer_list<basic_json>) -- create a JSON array
- value from an initializer list
-
- @since version 1.0.0
- */
- static basic_json object(std::initializer_list<basic_json> init =
- std::initializer_list<basic_json>())
- {
- return basic_json(init, false, value_t::object);
- }
-
- /*!
- @brief construct an array with count copies of given value
-
- 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.
-
- @param[in] cnt the number of JSON copies of @a val to create
- @param[in] val the JSON value to copy
-
- @complexity Linear in @a cnt.
-
- @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(size_type cnt, const basic_json &val) : m_type(value_t::array)
- {
- m_value.array = create<array_t>(cnt, val);
- assert_invariant();
- }
-
- /*!
- @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.
-
- @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)
-
- @pre Iterators @a first and @a last must be initialized. **This
- precondition is enforced with an assertion.**
-
- @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 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.
-
- @complexity Linear in distance between @a first and @a last.
-
- @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
- */
- template <
- class InputIT,
- typename std::enable_if<
- std::is_same<InputIT, typename basic_json_t::iterator>::value or
- std::is_same<InputIT,
- typename basic_json_t::const_iterator>::value,
- int>::type = 0>
- basic_json(InputIT first, InputIT last)
- {
- assert(first.m_object != nullptr);
- assert(last.m_object != nullptr);
-
- // 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;
- }
-
- case value_t::number_unsigned:
- {
- m_value.number_unsigned = first.m_object->m_value.number_unsigned;
- break;
- }
-
- case value_t::number_float:
- {
- m_value.number_float = first.m_object->m_value.number_float;
- break;
- }
-
- case value_t::boolean:
- {
- m_value.boolean = first.m_object->m_value.boolean;
- break;
- }
-
- case value_t::string:
- {
- m_value = *first.m_object->m_value.string;
- break;
- }
-
- case value_t::object:
- {
- m_value.object = create<object_t>(first.m_it.object_iterator,
- last.m_it.object_iterator);
- break;
- }
-
- case value_t::array:
- {
- m_value.array = create<array_t>(first.m_it.array_iterator,
- last.m_it.array_iterator);
- break;
- }
-
- default:
- {
- JSON_THROW(invalid_iterator::create(
- 206, "cannot construct with iterators from " +
- first.m_object->type_name()));
- }
- }
-
- assert_invariant();
- }
-
- ///////////////////////////////////////
- // other constructors and destructor //
- ///////////////////////////////////////
-
- /*!
- @brief copy constructor
-
- Creates a copy of a given JSON value.
-
- @param[in] other the JSON value to copy
-
- @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 following code shows an example for the copy
- constructor.,basic_json__basic_json}
-
- @since version 1.0.0
- */
- basic_json(const basic_json &other) : m_type(other.m_type)
- {
- // 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;
- }
-
- case value_t::string:
- {
- m_value = *other.m_value.string;
- break;
- }
-
- case value_t::boolean:
- {
- m_value = other.m_value.boolean;
- break;
- }
-
- case value_t::number_integer:
- {
- m_value = other.m_value.number_integer;
- break;
- }
-
- case value_t::number_unsigned:
- {
- m_value = other.m_value.number_unsigned;
- break;
- }
-
- case value_t::number_float:
- {
- m_value = other.m_value.number_float;
- break;
- }
-
- default:
- {
- break;
- }
- }
-
- assert_invariant();
- }
-
- /*!
- @brief move constructor
-
- 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,out] other value to move to this object
-
- @post @a other is a JSON null value
-
- @complexity Constant.
-
- @liveexample{The code below shows the move constructor explicitly called
- via std::move.,basic_json__moveconstructor}
-
- @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))
- {
- // check that passed value is valid
- other.assert_invariant();
-
- // invalidate payload
- other.m_type = value_t::null;
- other.m_value = {};
-
- assert_invariant();
- }
-
- /*!
- @brief copy assignment
-
- 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] other value to copy from
-
- @complexity Linear.
-
- @requirement This function helps `basic_json` satisfying the
- [Container](http://en.cppreference.com/w/cpp/concept/Container)
- requirements:
- - The complexity is linear.
-
- @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
- */
- reference &operator=(basic_json other) noexcept(
- std::is_nothrow_move_constructible<value_t>::value
- and std::is_nothrow_move_assignable<value_t>::value
- and std::is_nothrow_move_constructible<json_value>::value
- and std::is_nothrow_move_assignable<json_value>::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 destructor
-
- Destroys the JSON value and frees all allocated memory.
-
- @complexity Linear.
-
- @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 1.0.0
- */
- ~basic_json()
- {
- assert_invariant();
-
- switch (m_type)
- {
- case value_t::object:
- {
- AllocatorType<object_t> alloc;
- alloc.destroy(m_value.object);
- alloc.deallocate(m_value.object, 1);
- break;
- }
-
- case value_t::array:
- {
- AllocatorType<array_t> alloc;
- alloc.destroy(m_value.array);
- alloc.deallocate(m_value.array, 1);
- break;
- }
-
- case value_t::string:
- {
- AllocatorType<string_t> alloc;
- alloc.destroy(m_value.string);
- alloc.deallocate(m_value.string, 1);
- break;
- }
-
- default:
- {
- // all other types need no specific destructor
- break;
- }
- }
- }
-
- /// @}
-
-public:
- ///////////////////////
- // object inspection //
- ///////////////////////
-
- /// @name object inspection
- /// Functions to inspect the type of a JSON value.
- /// @{
-
- /*!
- @brief serialization
-
- Serialization function for JSON values. The function tries to mimic
- Python's `json.dumps()` function, and currently supports its @a indent
- parameter.
-
- @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.
-
- @return string containing the serialization of the JSON value
-
- @complexity Linear.
-
- @liveexample{The following example shows the effect of different @a indent
- parameters to the result of the serialization.,dump}
-
- @see https://docs.python.org/2/library/json.html#json.dump
-
- @since version 1.0.0
- */
- string_t dump(const int indent = -1) const
- {
- std::stringstream ss;
- serializer s(ss);
-
- if (indent >= 0)
- {
- s.dump(*this, true, static_cast<unsigned int>(indent));
- }
- else
- {
- s.dump(*this, false, 0);
- }
-
- return ss.str();
- }
-
- /*!
- @brief return the type of the JSON value (explicit)
-
- Return the type of the JSON value as a value from the @ref value_t
- enumeration.
-
- @return the type of the JSON value
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies `type()` for all JSON
- types.,type}
-
- @since version 1.0.0
- */
- constexpr value_t type() const noexcept { return m_type; }
-
- /*!
- @brief return whether type is primitive
-
- This function returns true iff the JSON type is primitive (string, number,
- boolean, or null).
-
- @return `true` if type is primitive (string, number, boolean, or null),
- `false` otherwise.
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies `is_primitive()` for all JSON
- types.,is_primitive}
-
- @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
- */
- constexpr bool is_primitive() const noexcept
- {
- return is_null() or is_string() or is_boolean() or is_number();
- }
-
- /*!
- @brief return whether type is structured
-
- This function returns true iff the JSON type is structured (array or
- object).
-
- @return `true` if type is structured (array or object), `false` otherwise.
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies `is_structured()` for all JSON
- types.,is_structured}
-
- @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
- */
- constexpr bool is_structured() const noexcept
- {
- return is_array() or is_object();
- }
-
- /*!
- @brief return whether value is null
-
- This function returns true iff the JSON value is null.
-
- @return `true` if type is null, `false` otherwise.
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies `is_null()` for all JSON
- types.,is_null}
-
- @since version 1.0.0
- */
- constexpr bool is_null() const noexcept { return m_type == value_t::null; }
-
- /*!
- @brief return whether value is a boolean
-
- 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
- */
- constexpr bool is_boolean() const noexcept
- {
- return m_type == value_t::boolean;
- }
-
- /*!
- @brief return whether value is a number
-
- This function returns true iff the JSON value is a number. This includes
- both integer and floating-point values.
-
- @return `true` if type is number (regardless whether integer, unsigned
- integer or floating-type), `false` otherwise.
-
- @complexity Constant.
-
- @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
- */
- constexpr bool is_number() const noexcept
- {
- return is_number_integer() or is_number_float();
- }
-
- /*!
- @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.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies `is_number_integer()` for all
- JSON types.,is_number_integer}
-
- @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
- */
- constexpr bool is_number_integer() const noexcept
- {
- return m_type == value_t::number_integer or
- m_type == value_t::number_unsigned;
- }
-
- /*!
- @brief return whether value is an unsigned integer number
-
- This function returns true iff the JSON value is an unsigned integer
- number. This excludes floating-point and (signed) integer values.
-
- @return `true` if type is an unsigned integer number, `false` otherwise.
-
- @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 2.0.0
- */
- constexpr bool is_number_unsigned() const noexcept
- {
- return m_type == value_t::number_unsigned;
- }
-
- /*!
- @brief return whether value is a floating-point number
-
- This function returns true iff the JSON value is a floating-point number.
- This excludes integer and unsigned integer values.
-
- @return `true` if type is a floating-point number, `false` otherwise.
-
- @complexity Constant.
-
- @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 return whether value is an object
-
- This function returns true iff the JSON value is an object.
-
- @return `true` if type is object, `false` otherwise.
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies `is_object()` for all JSON
- types.,is_object}
-
- @since version 1.0.0
- */
- constexpr bool is_object() const noexcept
- {
- return m_type == value_t::object;
- }
-
- /*!
- @brief return whether value is an array
-
- This function returns true iff the JSON value is an array.
-
- @return `true` if type is array, `false` otherwise.
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies `is_array()` for all JSON
- types.,is_array}
-
- @since version 1.0.0
- */
- constexpr bool is_array() const noexcept
- {
- return m_type == value_t::array;
- }
-
- /*!
- @brief return whether value is a string
-
- This function returns true iff the JSON value is a string.
-
- @return `true` if type is string, `false` otherwise.
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies `is_string()` for all JSON
- types.,is_string}
-
- @since version 1.0.0
- */
- constexpr bool is_string() const noexcept
- {
- return m_type == value_t::string;
- }
-
- /*!
- @brief return whether value is discarded
-
- This function returns true iff the JSON value was discarded during parsing
- with a callback function (see @ref parser_callback_t).
-
- @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.
-
- @return `true` if type is discarded, `false` otherwise.
-
- @complexity Constant.
-
- @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
- */
- constexpr bool is_discarded() const noexcept
- {
- return m_type == value_t::discarded;
- }
-
- /*!
- @brief return the type of the JSON value (implicit)
-
- Implicitly return the type of the JSON value as a value from the @ref
- value_t enumeration.
-
- @return the type of the JSON value
-
- @complexity Constant.
-
- @exceptionsafety No-throw guarantee: this member function never throws
- exceptions.
-
- @liveexample{The following code exemplifies the @ref value_t operator for
- all JSON types.,operator__value_t}
-
- @since version 1.0.0
- */
- constexpr operator value_t() const noexcept { return m_type; }
-
- /// @}
-
-private:
- //////////////////
- // value access //
- //////////////////
-
- /// get a boolean (explicit)
- boolean_t get_impl(boolean_t * /*unused*/) const
- {
- if (is_boolean())
- {
- return m_value.boolean;
- }
-
- JSON_THROW(type_error::create(302, "type must be boolean, but is " +
- type_name()));
- }
-
- /// get a pointer to the value (object)
- object_t *get_impl_ptr(object_t * /*unused*/) noexcept
- {
- return is_object() ? m_value.object : nullptr;
- }
-
- /// 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;
- }
-
- /// get a pointer to the value (array)
- array_t *get_impl_ptr(array_t * /*unused*/) noexcept
- {
- return is_array() ? m_value.array : nullptr;
- }
-
- /// 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;
- }
-
- /// get a pointer to the value (string)
- string_t *get_impl_ptr(string_t * /*unused*/) noexcept
- {
- return is_string() ? m_value.string : nullptr;
- }
-
- /// 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;
- }
-
- /// 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;
- }
-
- /// 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;
- }
-
- /// 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;
- }
-
- /// 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;
- }
-
- /// 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;
- }
-
- /// 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;
- }
-
- /// 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;
- }
-
- /*!
- @brief helper function to implement get_ref()
-
- This funcion helps to implement get_ref() without code duplication for
- const and non-const overloads
-
- @tparam ThisType will be deduced as `basic_json` or `const basic_json`
-
- @throw type_error.303 if ReferenceType does not match underlying value
- type of the current JSON
- */
- template <typename ReferenceType, typename ThisType>
- static ReferenceType get_ref_impl(ThisType &obj)
- {
- // helper type
- using PointerType = typename std::add_pointer<ReferenceType>::type;
-
- // delegate the call to get_ptr<>()
- auto ptr = obj.template get_ptr<PointerType>();
-
- if (ptr != nullptr)
- {
- return *ptr;
- }
-
- 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 get special-case overload
-
- This overloads avoids a lot of template boilerplate, it can be seen as the
- identity method
-
- @tparam BasicJsonType == @ref basic_json
-
- @return a copy of *this
-
- @complexity Constant.
-
- @since version 2.1.0
- */
- template <typename BasicJsonType,
- detail::enable_if_t<
- std::is_same<typename std::remove_const<BasicJsonType>::type,
- basic_json_t>::value,
- int> = 0>
- basic_json get() const
- {
- return *this;
- }
-
- /*!
- @brief get a value (explicit)
-
- 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<ValueType>
- `from_json()` method.
-
- The function is equivalent to executing
- @code {.cpp}
- ValueType ret;
- JSONSerializer<ValueType>::from_json(*this, ret);
- return ret;
- @endcode
-
- This overloads is chosen if:
- - @a ValueType is not @ref basic_json,
- - @ref json_serializer<ValueType> has a `from_json()` method of the form
- `void from_json(const @ref basic_json&, ValueType&)`, and
- - @ref json_serializer<ValueType> does not have a `from_json()` method of
- the form `ValueType from_json(const @ref 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<ValueType> `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<short>`\, (3) A JSON object can be converted to C++
- associative containers such as `std::unordered_map<std::string\,
- json>`.,get__ValueType_const}
-
- @since version 2.1.0
- */
- template <typename ValueTypeCV,
- typename ValueType = detail::uncvref_t<ValueTypeCV>,
- detail::enable_if_t<
- not std::is_same<basic_json_t, ValueType>::value and
- detail::has_from_json<basic_json_t, ValueType>::value and
- not detail::has_non_default_from_json<basic_json_t,
- ValueType>::value,
- int> = 0>
- ValueType get() const
- noexcept(noexcept(JSONSerializer<ValueType>::from_json(
- std::declval<const basic_json_t &>(), std::declval<ValueType &>())))
- {
- // we cannot static_assert on ValueTypeCV being non-const, because
- // there is support for get<const basic_json_t>(), which is why we
- // still need the uncvref
- static_assert(not std::is_reference<ValueTypeCV>::value,
- "get() cannot be used with reference types, you might "
- "want to use get_ref()");
- static_assert(
- std::is_default_constructible<ValueType>::value,
- "types must be DefaultConstructible when used with get()");
-
- ValueType ret;
- JSONSerializer<ValueType>::from_json(*this, ret);
- return ret;
- }
-
- /*!
- @brief get a value (explicit); special case
-
- 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<ValueType>
- `from_json()` method.
-
- The function is equivalent to executing
- @code {.cpp}
- return JSONSerializer<ValueTypeCV>::from_json(*this);
- @endcode
-
- This overloads is chosen if:
- - @a ValueType is not @ref basic_json and
- - @ref json_serializer<ValueType> has a `from_json()` method of the form
- `ValueType from_json(const @ref basic_json&)`
-
- @note If @ref json_serializer<ValueType> has both overloads of
- `from_json()`, this one is chosen.
-
- @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<ValueType> `from_json()` method throws
-
- @since version 2.1.0
- */
- template <
- typename ValueTypeCV,
- typename ValueType = detail::uncvref_t<ValueTypeCV>,
- detail::enable_if_t<not std::is_same<basic_json_t, ValueType>::value and
- detail::has_non_default_from_json<
- basic_json_t, ValueType>::value,
- int> = 0>
- ValueType get() const
- noexcept(noexcept(JSONSerializer<ValueTypeCV>::from_json(
- std::declval<const basic_json_t &>())))
- {
- static_assert(not std::is_reference<ValueTypeCV>::value,
- "get() cannot be used with reference types, you might "
- "want to use get_ref()");
- return JSONSerializer<ValueTypeCV>::from_json(*this);
- }
-
- /*!
- @brief get a pointer value (explicit)
-
- Explicit pointer access to the internally stored JSON value. No copies are
- made.
-
- @warning The pointer becomes invalid if the underlying JSON object
- changes.
-
- @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.
-
- @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__PointerType}
-
- @sa @ref get_ptr() for explicit pointer-member access
-
- @since version 1.0.0
- */
- template <typename PointerType,
- typename std::enable_if<std::is_pointer<PointerType>::value,
- int>::type = 0>
- PointerType get() noexcept
- {
- // delegate the call to get_ptr
- return get_ptr<PointerType>();
- }
-
- /*!
- @brief get a pointer value (explicit)
- @copydoc get()
- */
- template <typename PointerType,
- typename std::enable_if<std::is_pointer<PointerType>::value,
- int>::type = 0>
- constexpr const PointerType get() const noexcept
- {
- // delegate the call to get_ptr
- return get_ptr<PointerType>();
- }
-
- /*!
- @brief get a pointer value (implicit)
-
- Implicit pointer access to the internally stored JSON value. No copies are
- made.
-
- @warning Writing data to the pointee of the result yields an undefined
- state.
-
- @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.
-
- @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
- */
- template <typename PointerType,
- typename std::enable_if<std::is_pointer<PointerType>::value,
- int>::type = 0>
- PointerType get_ptr() noexcept
- {
- // get the type of the PointerType (remove pointer and const)
- using pointee_t =
- typename std::remove_const<typename std::remove_pointer<
- typename std::remove_const<PointerType>::type>::type>::type;
- // make sure the type matches the allowed types
- static_assert(std::is_same<object_t, pointee_t>::value or
- std::is_same<array_t, pointee_t>::value or
- std::is_same<string_t, pointee_t>::value or
- std::is_same<boolean_t, pointee_t>::value or
- std::is_same<number_integer_t, pointee_t>::value or
- std::is_same<number_unsigned_t, pointee_t>::value or
- std::is_same<number_float_t, pointee_t>::value,
- "incompatible pointer type");
-
- // delegate the call to get_impl_ptr<>()
- return get_impl_ptr(static_cast<PointerType>(nullptr));
- }
-
- /*!
- @brief get a pointer value (implicit)
- @copydoc get_ptr()
- */
- template <
- typename PointerType,
- typename std::enable_if<std::is_pointer<PointerType>::value and
- std::is_const<typename std::remove_pointer<
- PointerType>::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<typename std::remove_pointer<
- typename std::remove_const<PointerType>::type>::type>::type;
- // make sure the type matches the allowed types
- static_assert(std::is_same<object_t, pointee_t>::value or
- std::is_same<array_t, pointee_t>::value or
- std::is_same<string_t, pointee_t>::value or
- std::is_same<boolean_t, pointee_t>::value or
- std::is_same<number_integer_t, pointee_t>::value or
- std::is_same<number_unsigned_t, pointee_t>::value or
- std::is_same<number_float_t, pointee_t>::value,
- "incompatible pointer type");
-
- // delegate the call to get_impl_ptr<>() const
- return get_impl_ptr(static_cast<const PointerType>(nullptr));
- }
-
- /*!
- @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.
-
- @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
-
- @throw type_error.303 in case passed type @a ReferenceType is incompatible
- with the stored JSON value; see example below
-
- @complexity Constant.
-
- @liveexample{The example shows several calls to `get_ref()`.,get_ref}
-
- @since version 1.1.0
- */
- template <typename ReferenceType,
- typename std::enable_if<std::is_reference<ReferenceType>::value,
- int>::type = 0>
- ReferenceType get_ref()
- {
- // delegate call to get_ref_impl
- return get_ref_impl<ReferenceType>(*this);
- }
-
- /*!
- @brief get a reference value (implicit)
- @copydoc get_ref()
- */
- template <typename ReferenceType,
- typename std::enable_if<
- std::is_reference<ReferenceType>::value and
- std::is_const<typename std::remove_reference<
- ReferenceType>::type>::value,
- int>::type = 0>
- ReferenceType get_ref() const
- {
- // delegate call to get_ref_impl
- return get_ref_impl<ReferenceType>(*this);
- }
-
- /*!
- @brief get a value (implicit)
-
- Implicit type conversion between the JSON value and a compatible value.
- The call is realized by calling @ref get() const.
-
- @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 copy of the JSON value, converted to type @a ValueType
-
- @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
-
- @complexity Linear in the size of the JSON value.
-
- @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<short>`\, (3) A JSON object can be converted to C++
- associative containers such as `std::unordered_map<std::string\,
- json>`.,operator__ValueType}
-
- @since version 1.0.0
- */
- template <
- typename ValueType,
- typename std::enable_if<
- not std::is_pointer<ValueType>::value and
- not std::is_same<ValueType,
- typename string_t::value_type>::value
-#ifndef _MSC_VER // fix for issue #167 operator<< ambiguity under VS2015
- and
- not std::is_same<
- ValueType,
- std::initializer_list<typename string_t::value_type>>::value
-#endif
-#if defined(_MSC_VER) && defined(_HAS_CXX17) && \
- _HAS_CXX17 == 1 // fix for issue #464
- and
- not std::is_same<ValueType, typename std::string_view>::value
-#endif
- ,
- int>::type = 0>
- operator ValueType() const
- {
- // delegate the call to get<>() const
- return get<ValueType>();
- }
-
- /// @}
-
- ////////////////////
- // element access //
- ////////////////////
-
- /// @name element access
- /// Access to the JSON value.
- /// @{
-
- /*!
- @brief access specified array element with bounds checking
-
- Returns a reference to the element at specified location @a idx, with
- bounds checking.
-
- @param[in] idx index of the element to access
-
- @return reference to the element at index @a idx
-
- @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.
-
- @exceptionsafety Strong guarantee: if an exception is thrown, there are no
- changes in the JSON value.
-
- @complexity Constant.
-
- @since version 1.0.0
-
- @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}
- */
- reference at(size_type idx)
- {
- // 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 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
-
- @return const reference to the element at index @a idx
-
- @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.
-
- @exceptionsafety Strong guarantee: if an exception is thrown, there are no
- changes in the JSON value.
-
- @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}
- */
- const_reference at(size_type idx) const
- {
- // 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 access specified object element with bounds checking
-
- Returns a reference to the element at with specified key @a key, with
- bounds checking.
-
- @param[in] key key of the element to access
-
- @return reference to the element at key @a key
-
- @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.
-
- @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}
- */
- reference at(const typename object_t::key_type &key)
- {
- // 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 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
-
- @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.
-
- @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}
- */
- const_reference at(const typename object_t::key_type &key) const
- {
- // 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 access specified array element
-
- Returns a reference to the element at specified location @a idx.
-
- @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] idx index of the element to access
-
- @return reference to the element at index @a idx
-
- @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
- */
- reference operator[](size_type idx)
- {
- // implicitly convert null value to an empty array
- if (is_null())
- {
- m_type = value_t::array;
- m_value.array = create<array_t>();
- 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 access specified array element
-
- Returns a const reference to the element at specified location @a idx.
-
- @param[in] idx index of the element to access
-
- @return const reference to the element at index @a idx
-
- @throw type_error.305 if the JSON value is not an array; in that cases,
- using the [] operator with an index makes no sense.
-
- @complexity Constant.
-
- @liveexample{The example below shows how array elements can be read using
- the `[]` operator.,operatorarray__size_type_const}
-
- @since version 1.0.0
- */
- const_reference operator[](size_type idx) const
- {
- // 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 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.
-
- @param[in] key key of the element to access
-
- @return reference to the element at key @a key
-
- @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 1.0.0
- */
- reference operator[](const 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<object_t>();
- assert_invariant();
- }
-
- // operator[] only works for objects
- if (is_object())
- {
- return m_value.object->operator[](key);
- }
-
- JSON_THROW(type_error::create(305, "cannot use operator[] with " +
- type_name()));
- }
-
- /*!
- @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.
-
- @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
-
- @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
- {
- // 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;
- }
-
- JSON_THROW(type_error::create(305, "cannot use operator[] with " +
- type_name()));
- }
-
- /*!
- @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.
-
- @param[in] key key of the element to access
-
- @return reference to the element at key @a key
-
- @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 1.0.0
- */
- template <typename T, std::size_t n>
- reference operator[](T *(&key)[n])
- {
- return operator[](static_cast<const T>(key));
- }
-
- /*!
- @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.
-
- @warning If the element with key @a key does not exist, the behavior is
- undefined.
-
- @note This function is required for compatibility reasons with Clang.
-
- @param[in] key key of the element to access
-
- @return const reference to the element at key @a key
-
- @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
- */
- template <typename T, std::size_t n>
- const_reference operator[](T *(&key)[n]) const
- {
- return operator[](static_cast<const T>(key));
- }
-
- /*!
- @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.
-
- @param[in] key key of the element to access
-
- @return reference to the element at key @a key
-
- @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 <typename T>
- reference operator[](T *key)
- {
- // implicitly convert null to object
- if (is_null())
- {
- m_type = value_t::object;
- m_value = value_t::object;
- assert_invariant();
- }
-
- // at only works for objects
- if (is_object())
- {
- return m_value.object->operator[](key);
- }
-
- JSON_THROW(type_error::create(305, "cannot use operator[] with " +
- type_name()));
- }
-
- /*!
- @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.
-
- @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
-
- @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 1.1.0
- */
- template <typename T>
- const_reference operator[](T *key) const
- {
- // 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 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(out_of_range) {
- return default_value;
- }
- @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
-
- @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.
-
- @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 <
- class ValueType,
- typename std::enable_if<
- std::is_convertible<basic_json_t, ValueType>::value, int>::type = 0>
- ValueType value(const typename object_t::key_type &key,
- ValueType default_value) const
- {
- // 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 overload for a default value of type const char*
- @copydoc basic_json::value(const typename object_t::key_type&, ValueType)
- const
- */
- string_t value(const typename object_t::key_type &key,
- const char *default_value) const
- {
- return value(key, string_t(default_value));
- }
-
- /*!
- @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(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.
-
- @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_ptr}
-
- @sa @ref operator[](const json_pointer&) for unchecked access by reference
-
- @since version 2.0.2
- */
- template <
- class ValueType,
- typename std::enable_if<
- std::is_convertible<basic_json_t, ValueType>::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
- JSON_TRY { return ptr.get_checked(this); }
- JSON_CATCH(out_of_range &) { return default_value; }
- }
-
- JSON_THROW(
- type_error::create(306, "cannot use value() with " + type_name()));
- }
-
- /*!
- @brief overload for a default value of type const char*
- @copydoc basic_json::value(const json_pointer&, ValueType) const
- */
- string_t value(const json_pointer &ptr, const char *default_value) const
- {
- return value(ptr, string_t(default_value));
- }
-
- /*!
- @brief access the first element
-
- Returns a reference to the first element in the container. For a JSON
- container `c`, the expression `c.front()` is equivalent to `*c.begin()`.
-
- @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.
-
- @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 invalid_iterator.214 when called on `null` value
-
- @liveexample{The following code shows an example for `front()`.,front}
-
- @sa @ref back() -- access the last element
-
- @since version 1.0.0
- */
- reference front() { return *begin(); }
-
- /*!
- @copydoc basic_json::front()
- */
- const_reference front() const { return *cbegin(); }
-
- /*!
- @brief access the last element
-
- 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
-
- @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.
-
- @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 invalid_iterator.214 when called on a `null` value. See example
- below.
-
- @liveexample{The following code shows an example for `back()`.,back}
-
- @sa @ref front() -- access the first element
-
- @since version 1.0.0
- */
- reference back()
- {
- 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
-
- 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.
-
- If called on a primitive type other than `null`, the resulting JSON value
- will be `null`.
-
- @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.
-
- @tparam IteratorType an @ref iterator or @ref const_iterator
-
- @post Invalidates iterators and references at or after the point of the
- erase, including the `end()` iterator.
-
- @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"`
-
- @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
-
- @liveexample{The example shows the result of `erase()` for different JSON
- types.,erase__IteratorType}
-
- @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
- */
- template <
- class IteratorType,
- typename std::enable_if<
- std::is_same<IteratorType,
- typename basic_json_t::iterator>::value or
- std::is_same<IteratorType,
- typename basic_json_t::const_iterator>::value,
- int>::type = 0>
- IteratorType erase(IteratorType pos)
- {
- // make sure iterator fits the current value
- if (this != pos.m_object)
- {
- JSON_THROW(invalid_iterator::create(
- 202, "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:
- {
- if (not pos.m_it.primitive_iterator.is_begin())
- {
- JSON_THROW(
- invalid_iterator::create(205, "iterator out of range"));
- }
-
- if (is_string())
- {
- AllocatorType<string_t> alloc;
- alloc.destroy(m_value.string);
- alloc.deallocate(m_value.string, 1);
- m_value.string = nullptr;
- }
-
- m_type = value_t::null;
- assert_invariant();
- break;
- }
-
- case value_t::object:
- {
- result.m_it.object_iterator =
- m_value.object->erase(pos.m_it.object_iterator);
- break;
- }
-
- case value_t::array:
- {
- result.m_it.array_iterator =
- m_value.array->erase(pos.m_it.array_iterator);
- break;
- }
-
- default:
- {
- JSON_THROW(type_error::create(307, "cannot use erase() with " +
- type_name()));
- }
- }
-
- 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.
-
- @tparam IteratorType an @ref iterator or @ref const_iterator
-
- @post Invalidates iterators and references at or after the point of the
- erase, including the `end()` iterator.
-
- @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"`
-
- @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
- */
- template <
- class IteratorType,
- typename std::enable_if<
- std::is_same<IteratorType,
- typename basic_json_t::iterator>::value or
- std::is_same<IteratorType,
- typename basic_json_t::const_iterator>::value,
- int>::type = 0>
- IteratorType erase(IteratorType first, IteratorType last)
- {
- // make sure iterator fits the current value
- if (this != first.m_object or this != last.m_object)
- {
- JSON_THROW(invalid_iterator::create(
- 203, "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:
- 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"));
- }
-
- if (is_string())
- {
- AllocatorType<string_t> alloc;
- alloc.destroy(m_value.string);
- alloc.deallocate(m_value.string, 1);
- m_value.string = nullptr;
- }
-
- m_type = value_t::null;
- assert_invariant();
- break;
- }
-
- case value_t::object:
- {
- result.m_it.object_iterator = m_value.object->erase(
- first.m_it.object_iterator, last.m_it.object_iterator);
- break;
- }
-
- case value_t::array:
- {
- result.m_it.array_iterator = m_value.array->erase(
- first.m_it.array_iterator, last.m_it.array_iterator);
- break;
- }
-
- default:
- {
- JSON_THROW(type_error::create(307, "cannot use erase() with " +
- type_name()));
- }
- }
-
- 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).
-
- @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"`
-
- @complexity `log(size()) + count(key)`
-
- @liveexample{The example shows the effect of `erase()`.,erase__key_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
- */
- size_type erase(const typename object_t::key_type &key)
- {
- // this erase only works for objects
- if (is_object())
- {
- return m_value.object->erase(key);
- }
-
- JSON_THROW(
- type_error::create(307, "cannot use erase() with " + type_name()));
- }
-
- /*!
- @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 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"`
-
- @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
-
- @since version 1.0.0
- */
- void erase(const size_type idx)
- {
- // this erase only works for arrays
- if (is_array())
- {
- 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<difference_type>(idx));
- }
- else
- {
- JSON_THROW(type_error::create(307, "cannot use erase() with " +
- type_name()));
- }
- }
-
- /// @}
-
- ////////////
- // lookup //
- ////////////
-
- /// @name lookup
- /// @{
-
- /*!
- @brief find an element in a JSON 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.
-
- @note This method always returns @ref end() when executed on a JSON type
- that is not an object.
-
- @param[in] key key value of the element to search for
-
- @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.
-
- @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
- */
- iterator find(typename object_t::key_type key)
- {
- auto result = end();
-
- if (is_object())
- {
- result.m_it.object_iterator = m_value.object->find(key);
- }
-
- return result;
- }
-
- /*!
- @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();
-
- if (is_object())
- {
- result.m_it.object_iterator = m_value.object->find(key);
- }
-
- return result;
- }
-
- /*!
- @brief returns the number of occurrences of a key in a JSON 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).
-
- @note This method always returns `0` when executed on a JSON type that is
- not an object.
-
- @param[in] key key value of the element to count
-
- @return Number of elements with key @a key. If the JSON value is not an
- object, the return value will be `0`.
-
- @complexity Logarithmic in the size of the JSON object.
-
- @liveexample{The example shows how `count()` is used.,count}
-
- @since version 1.0.0
- */
- size_type count(typename object_t::key_type key) const
- {
- // return 0 for all nonobject types
- return is_object() ? m_value.object->count(key) : 0;
- }
-
- /// @}
-
- ///////////////
- // iterators //
- ///////////////
-
- /// @name iterators
- /// @{
-
- /*!
- @brief returns an iterator to the first element
-
- Returns an iterator to the first element.
-
- @image html range-begin-end.svg "Illustration from cppreference.com"
-
- @return iterator to the first 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.
-
- @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
- */
- iterator begin() noexcept
- {
- iterator result(this);
- result.set_begin();
- return result;
- }
-
- /*!
- @copydoc basic_json::cbegin()
- */
- const_iterator begin() const noexcept { return cbegin(); }
-
- /*!
- @brief returns a const iterator to the first element
-
- Returns a const iterator to the first element.
-
- @image html range-begin-end.svg "Illustration from cppreference.com"
-
- @return const iterator to the first 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<const basic_json&>(*this).begin()`.
-
- @liveexample{The following code shows an example for `cbegin()`.,cbegin}
-
- @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
- */
- const_iterator cbegin() const noexcept
- {
- const_iterator result(this);
- result.set_begin();
- return result;
- }
-
- /*!
- @brief returns an iterator to one past the last element
-
- Returns an iterator to one past the last element.
-
- @image html range-begin-end.svg "Illustration from cppreference.com"
-
- @return 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.
-
- @liveexample{The following code shows an example for `end()`.,end}
-
- @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 1.0.0
- */
- iterator end() noexcept
- {
- iterator result(this);
- result.set_end();
- return result;
- }
-
- /*!
- @copydoc basic_json::cend()
- */
- const_iterator end() const noexcept { return cend(); }
-
- /*!
- @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<const basic_json&>(*this).end()`.
-
- @liveexample{The following code shows an example for `cend()`.,cend}
-
- @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
-
- @since version 1.0.0
- */
- const_iterator cend() const noexcept
- {
- const_iterator result(this);
- result.set_end();
- return result;
- }
-
- /*!
- @brief returns an iterator to the reverse-beginning
-
- Returns an iterator to the reverse-beginning; that is, the last element.
-
- @image html range-rbegin-rend.svg "Illustration from cppreference.com"
-
- @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 `reverse_iterator(end())`.
-
- @liveexample{The following code shows an example for `rbegin()`.,rbegin}
-
- @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 1.0.0
- */
- reverse_iterator rbegin() noexcept { return reverse_iterator(end()); }
-
- /*!
- @copydoc basic_json::crbegin()
- */
- const_reverse_iterator rbegin() const noexcept { return crbegin(); }
-
- /*!
- @brief returns an iterator to the reverse-end
-
- Returns an iterator to the reverse-end; that is, one before the first
- element.
-
- @image html range-rbegin-rend.svg "Illustration from cppreference.com"
-
- @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 `reverse_iterator(begin())`.
-
- @liveexample{The following code shows an example for `rend()`.,rend}
-
- @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
- */
- reverse_iterator rend() noexcept { return reverse_iterator(begin()); }
-
- /*!
- @copydoc basic_json::crend()
- */
- const_reverse_iterator rend() const noexcept { return crend(); }
-
- /*!
- @brief returns a const reverse iterator to the last element
-
- Returns a const iterator to the reverse-beginning; that is, the last
- element.
-
- @image html range-rbegin-rend.svg "Illustration from cppreference.com"
-
- @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<const basic_json&>(*this).rbegin()`.
-
- @liveexample{The following code shows an example for `crbegin()`.,crbegin}
-
- @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
-
- @since version 1.0.0
- */
- const_reverse_iterator crbegin() const noexcept
- {
- return const_reverse_iterator(cend());
- }
-
- /*!
- @brief returns a const reverse iterator to one before the first
-
- Returns a const reverse iterator to the reverse-end; that is, one before
- the first element.
-
- @image html range-rbegin-rend.svg "Illustration from cppreference.com"
-
- @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<const basic_json&>(*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
-
- @since version 1.0.0
- */
- const_reverse_iterator crend() const noexcept
- {
- return const_reverse_iterator(cbegin());
- }
-
-private:
- // forward declaration
- template <typename IteratorType>
- 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.
-
- @note The name of this function is not yet final and may change in the
- future.
- */
- static iteration_proxy<iterator> iterator_wrapper(reference cont)
- {
- return iteration_proxy<iterator>(cont);
- }
-
- /*!
- @copydoc iterator_wrapper(reference)
- */
- static iteration_proxy<const_iterator>
- iterator_wrapper(const_reference cont)
- {
- return iteration_proxy<const_iterator>(cont);
- }
-
- /// @}
-
- //////////////
- // capacity //
- //////////////
-
- /// @name capacity
- /// @{
-
- /*!
- @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()`
-
- @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.
-
- @complexity Constant, as long as @ref array_t and @ref object_t satisfy
- the Container concept; that is, their `empty()` 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 `begin() == end()`.
-
- @liveexample{The following code uses `empty()` to check if a JSON
- object contains any elements.,empty}
-
- @sa @ref size() -- returns the number of elements
-
- @since version 1.0.0
- */
- bool empty() const noexcept
- {
- switch (m_type)
- {
- 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;
- }
- }
- }
-
- /*!
- @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()
-
- @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.
-
- @complexity Constant, as long as @ref array_t and @ref object_t satisfy
- the Container concept; that is, their 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 `std::distance(begin(), end())`.
-
- @liveexample{The following code calls `size()` on the different value
- types.,size}
-
- @sa @ref empty() -- checks whether the container is empty
- @sa @ref max_size() -- returns the maximal number of elements
-
- @since version 1.0.0
- */
- size_type size() const noexcept
- {
- switch (m_type)
- {
- case value_t::null:
- {
- // null values are empty
- return 0;
- }
-
- 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();
- }
-
- 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:
- {
- // 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:
- {
- // all other types have max_size() == size()
- return size();
- }
- }
- }
-
- /// @}
-
- ///////////////
- // modifiers //
- ///////////////
-
- /// @name modifiers
- /// @{
-
- /*!
- @brief clears the contents
-
- 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:
-
- Value type | initial value
- ----------- | -------------
- null | `null`
- boolean | `false`
- string | `""`
- number | `0`
- object | `{}`
- array | `[]`
-
- @complexity Linear in the size of the JSON value.
-
- @liveexample{The example below shows the effect of `clear()` to different
- JSON types.,clear}
-
- @since version 1.0.0
- */
- void clear() noexcept
- {
- switch (m_type)
- {
- case value_t::number_integer:
- {
- m_value.number_integer = 0;
- break;
- }
-
- case value_t::number_unsigned:
- {
- m_value.number_unsigned = 0;
- break;
- }
-
- case value_t::number_float:
- {
- m_value.number_float = 0.0;
- break;
- }
-
- case value_t::boolean:
- {
- m_value.boolean = false;
- break;
- }
-
- case value_t::string:
- {
- m_value.string->clear();
- break;
- }
-
- case value_t::array:
- {
- m_value.array->clear();
- break;
- }
-
- case value_t::object:
- {
- m_value.object->clear();
- break;
- }
-
- default:
- {
- break;
- }
- }
- }
-
- /*!
- @brief add an object to an array
-
- 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.
-
- @param[in] val the value to add to the JSON array
-
- @throw type_error.308 when called on a type other than JSON array or
- null; example: `"cannot use push_back() with number"`
-
- @complexity Amortized constant.
-
- @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
- */
- void push_back(basic_json &&val)
- {
- // push_back only works for null objects or arrays
- if (not(is_null() or is_array()))
- {
- JSON_THROW(type_error::create(308, "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;
- }
-
- /*!
- @brief add an object to an array
- @copydoc push_back(basic_json&&)
- */
- reference operator+=(basic_json &&val)
- {
- push_back(std::move(val));
- return *this;
- }
-
- /*!
- @brief add an object to an array
- @copydoc push_back(basic_json&&)
- */
- void push_back(const basic_json &val)
- {
- // push_back only works for null objects or arrays
- if (not(is_null() or is_array()))
- {
- JSON_THROW(type_error::create(308, "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
- m_value.array->push_back(val);
- }
-
- /*!
- @brief add an object to an array
- @copydoc push_back(basic_json&&)
- */
- reference operator+=(const basic_json &val)
- {
- push_back(val);
- return *this;
- }
-
- /*!
- @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.
-
- @param[in] val the value to add to the JSON object
-
- @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 container, O(log(`size()`)).
-
- @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
- */
- 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()))
- {
- JSON_THROW(type_error::create(308, "cannot use push_back() with " +
- type_name()));
- }
-
- // transform null object into an object
- if (is_null())
- {
- m_type = value_t::object;
- m_value = value_t::object;
- assert_invariant();
- }
-
- // add element to array
- m_value.object->insert(val);
- }
-
- /*!
- @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)
- {
- push_back(val);
- return *this;
- }
-
- /*!
- @brief add an object to an object
-
- This function allows to use `push_back` with an initializer list. In case
-
- 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,
-
- @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&&).
-
- @param[in] init an initializer list
-
- @complexity Linear in the size of the initializer list @a init.
-
- @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<basic_json>`, 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}
- */
- void push_back(std::initializer_list<basic_json> init)
- {
- 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));
- }
- }
-
- /*!
- @brief add an object to an object
- @copydoc push_back(std::initializer_list<basic_json>)
- */
- reference operator+=(std::initializer_list<basic_json> init)
- {
- push_back(init);
- return *this;
- }
-
- /*!
- @brief add an object to an array
-
- 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.
-
- @param[in] args arguments to forward to a constructor of @ref basic_json
- @tparam Args compatible types to create a @ref basic_json object
-
- @throw type_error.311 when called on a type other than JSON array or
- null; example: `"cannot use emplace_back() with number"`
-
- @complexity Amortized constant.
-
- @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 2.0.8
- */
- template <class... Args>
- void emplace_back(Args &&... args)
- {
- // 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()));
- }
-
- // 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>(args)...);
- }
-
- /*!
- @brief add an object to an object if key does not exist
-
- 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.
-
- @param[in] args arguments to forward to a constructor of @ref basic_json
- @tparam Args compatible types to create a @ref basic_json object
-
- @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.
-
- @throw type_error.311 when called on a type other than JSON object or
- null; example: `"cannot use emplace() with number"`
-
- @complexity Logarithmic in the size of the container, O(log(`size()`)).
-
- @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 2.0.8
- */
- template <class... Args>
- std::pair<iterator, bool> emplace(Args &&... args)
- {
- // 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()));
- }
-
- // transform null object into an object
- if (is_null())
- {
- m_type = value_t::object;
- m_value = value_t::object;
- assert_invariant();
- }
-
- // add element to array (perfect forwarding)
- auto res = m_value.object->emplace(std::forward<Args>(args)...);
- // create result iterator and set iterator to the result of emplace
- auto it = begin();
- it.m_it.object_iterator = res.first;
-
- // return pair of iterator and boolean
- return {it, res.second};
- }
-
- /*!
- @brief inserts element
-
- Inserts element @a val before iterator @a pos.
-
- @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.
-
- @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"`
-
- @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 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)
- {
- 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()));
- }
-
- /*!
- @brief inserts element
- @copydoc insert(const_iterator, const basic_json&)
- */
- iterator insert(const_iterator pos, basic_json &&val)
- {
- return insert(pos, val);
- }
-
- /*!
- @brief inserts elements
-
- Inserts @a cnt copies of @a val before iterator @a pos.
-
- @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`
-
- @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"`
-
- @complexity Linear in @a cnt plus linear in the distance between @a pos
- and end of the container.
-
- @liveexample{The example shows how `insert()` is used.,insert__count}
-
- @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())
- {
- // 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 inserts elements
-
- Inserts elements from range `[first, last)` before iterator @a pos.
-
- @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
-
- @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"`
-
- @return iterator pointing to the first element inserted, or @a pos if
- `first==last`
-
- @complexity Linear in `std::distance(first, last)` plus linear in the
- distance between @a pos and end of the container.
-
- @liveexample{The example shows how `insert()` is used.,insert__range}
-
- @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())
- {
- JSON_THROW(type_error::create(309, "cannot use insert() with " +
- type_name()));
- }
-
- // 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 inserts elements
-
- Inserts elements from initializer list @a ilist before iterator @a pos.
-
- @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
-
- @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"`
-
- @return iterator pointing to the first element inserted, or @a pos if
- `ilist` is empty
-
- @complexity Linear in `ilist.size()` plus linear in the distance between
- @a pos and end of the container.
-
- @liveexample{The example shows how `insert()` is used.,insert__ilist}
-
- @since version 1.0.0
- */
- iterator insert(const_iterator pos, std::initializer_list<basic_json> ilist)
- {
- // insert only works for arrays
- if (not is_array())
- {
- JSON_THROW(type_error::create(309, "cannot use insert() with " +
- type_name()));
- }
-
- // 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 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.
-
- @param[in,out] other JSON value to exchange the contents with
-
- @complexity Constant.
-
- @liveexample{The example below shows how JSON values can be swapped with
- `swap()`.,swap__reference}
-
- @since version 1.0.0
- */
- void swap(reference other) noexcept(
- std::is_nothrow_move_constructible<value_t>::value
- and std::is_nothrow_move_assignable<value_t>::value
- and std::is_nothrow_move_constructible<json_value>::value
- and std::is_nothrow_move_assignable<json_value>::value)
- {
- std::swap(m_type, other.m_type);
- std::swap(m_value, other.m_value);
- assert_invariant();
- }
-
- /*!
- @brief exchanges the values
-
- 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.
-
- @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.
-
- @liveexample{The example below shows how arrays can be swapped with
- `swap()`.,swap__array_t}
-
- @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 exchanges the values
-
- 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.
-
- @param[in,out] other object to exchange the contents with
-
- @throw type_error.310 when JSON value is not an object; example:
- `"cannot use swap() with string"`
-
- @complexity Constant.
-
- @liveexample{The example below shows how objects can be swapped with
- `swap()`.,swap__object_t}
-
- @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
- {
- JSON_THROW(type_error::create(310, "cannot use swap() with " +
- type_name()));
- }
- }
-
- /*!
- @brief exchanges the values
-
- 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.
-
- @param[in,out] other string to exchange the contents with
-
- @throw type_error.310 when JSON value is not a string; example: `"cannot
- use swap() with boolean"`
-
- @complexity Constant.
-
- @liveexample{The example below shows how strings can be swapped with
- `swap()`.,swap__string_t}
-
- @since version 1.0.0
- */
- void swap(string_t &other)
- {
- // swap only works for strings
- if (is_string())
- {
- std::swap(*(m_value.string), other);
- }
- else
- {
- JSON_THROW(type_error::create(310, "cannot use swap() with " +
- type_name()));
- }
- }
-
- /// @}
-
-public:
- //////////////////////////////////////////
- // lexicographical comparison operators //
- //////////////////////////////////////////
-
- /// @name lexicographical comparison operators
- /// @{
-
- /*!
- @brief comparison: equal
-
- 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.
-
- @note NaN values never compare equal to themselves or to other NaN values.
-
- @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
-
- @complexity Linear.
-
- @liveexample{The example demonstrates comparing several JSON
- types.,operator__equal}
-
- @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();
-
- 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<number_float_t>(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<number_float_t>(rhs.m_value.number_integer);
- }
- else if (lhs_type == value_t::number_unsigned and
- rhs_type == value_t::number_float)
- {
- return static_cast<number_float_t>(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<number_float_t>(rhs.m_value.number_unsigned);
- }
- else if (lhs_type == value_t::number_unsigned and
- rhs_type == value_t::number_integer)
- {
- return static_cast<number_integer_t>(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<number_integer_t>(rhs.m_value.number_unsigned);
- }
-
- return false;
- }
-
- /*!
- @brief comparison: equal
- @copydoc operator==(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::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 <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::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)`.
-
- @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
-
- @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 comparison: not equal
- @copydoc operator!=(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator!=(const_reference lhs, const ScalarType rhs) noexcept
- {
- return (lhs != basic_json(rhs));
- }
-
- /*!
- @brief comparison: not equal
- @copydoc operator!=(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator!=(const ScalarType lhs, const_reference rhs) noexcept
- {
- return (basic_json(lhs) != rhs);
- }
-
- /*!
- @brief comparison: less than
-
- 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).
-
- @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
-
- @complexity Linear.
-
- @liveexample{The example demonstrates comparing several JSON
- types.,operator__less}
-
- @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();
-
- 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<number_float_t>(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<number_float_t>(rhs.m_value.number_integer);
- }
- else if (lhs_type == value_t::number_unsigned and
- rhs_type == value_t::number_float)
- {
- return static_cast<number_float_t>(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<number_float_t>(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<number_integer_t>(rhs.m_value.number_unsigned);
- }
- else if (lhs_type == value_t::number_unsigned and
- rhs_type == value_t::number_integer)
- {
- return static_cast<number_integer_t>(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);
- }
-
- /*!
- @brief comparison: less than
- @copydoc operator<(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator<(const_reference lhs, const ScalarType rhs) noexcept
- {
- return (lhs < basic_json(rhs));
- }
-
- /*!
- @brief comparison: less than
- @copydoc operator<(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator<(const ScalarType lhs, const_reference rhs) noexcept
- {
- return (basic_json(lhs) < rhs);
- }
-
- /*!
- @brief comparison: less than or equal
-
- Compares whether one JSON value @a lhs is less than or equal to another
- JSON value by calculating `not (rhs < lhs)`.
-
- @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
-
- @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 comparison: less than or equal
- @copydoc operator<=(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator<=(const_reference lhs, const ScalarType rhs) noexcept
- {
- return (lhs <= basic_json(rhs));
- }
-
- /*!
- @brief comparison: less than or equal
- @copydoc operator<=(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator<=(const ScalarType lhs, const_reference rhs) noexcept
- {
- return (basic_json(lhs) <= rhs);
- }
-
- /*!
- @brief comparison: greater than
-
- Compares whether one JSON value @a lhs is greater than 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 to @a rhs
-
- @complexity Linear.
-
- @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);
- }
-
- /*!
- @brief comparison: greater than
- @copydoc operator>(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator>(const_reference lhs, const ScalarType rhs) noexcept
- {
- return (lhs > basic_json(rhs));
- }
-
- /*!
- @brief comparison: greater than
- @copydoc operator>(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator>(const ScalarType lhs, const_reference rhs) noexcept
- {
- return (basic_json(lhs) > rhs);
- }
-
- /*!
- @brief comparison: greater than or equal
-
- 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 comparison: greater than or equal
- @copydoc operator>=(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator>=(const_reference lhs, const ScalarType rhs) noexcept
- {
- return (lhs >= basic_json(rhs));
- }
-
- /*!
- @brief comparison: greater than or equal
- @copydoc operator>=(const_reference, const_reference)
- */
- template <typename ScalarType,
- typename std::enable_if<std::is_scalar<ScalarType>::value,
- int>::type = 0>
- friend bool operator>=(const ScalarType lhs, const_reference rhs) noexcept
- {
- return (basic_json(lhs) >= rhs);
- }
-
- /// @}
-
- ///////////////////
- // serialization //
- ///////////////////
-
- /// @name serialization
- /// @{
-
-private:
- /*!
- @brief wrapper around the serialization functions
- */
- class serializer
- {
- private:
- serializer(const serializer &) = delete;
- serializer &operator=(const serializer &) = delete;
-
- public:
- /*!
- @param[in] s output stream to serialize to
- */
- serializer(std::ostream &s)
- : 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])
- {
- }
-
- /*!
- @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.
-
- - 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("{}", 2);
- return;
- }
-
- if (pretty_print)
- {
- o.write("{\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(indent_string.c_str(),
- static_cast<std::streamsize>(new_indent));
- o.put('\"');
- dump_escaped(i->first);
- o.write("\": ", 3);
- dump(i->second, true, indent_step, new_indent);
- o.write(",\n", 2);
- }
-
- // last element
- assert(i != val.m_value.object->cend());
- o.write(indent_string.c_str(),
- static_cast<std::streamsize>(new_indent));
- o.put('\"');
- dump_escaped(i->first);
- o.write("\": ", 3);
- dump(i->second, true, indent_step, new_indent);
-
- o.put('\n');
- o.write(indent_string.c_str(),
- static_cast<std::streamsize>(current_indent));
- o.put('}');
- }
- else
- {
- o.put('{');
-
- // 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.put('\"');
- dump_escaped(i->first);
- o.write("\":", 2);
- dump(i->second, false, indent_step, current_indent);
- o.put(',');
- }
-
- // last element
- assert(i != val.m_value.object->cend());
- o.put('\"');
- dump_escaped(i->first);
- o.write("\":", 2);
- dump(i->second, false, indent_step, current_indent);
-
- o.put('}');
- }
-
- return;
- }
-
- case value_t::array:
- {
- if (val.m_value.array->empty())
- {
- o.write("[]", 2);
- return;
- }
-
- if (pretty_print)
- {
- o.write("[\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(indent_string.c_str(),
- static_cast<std::streamsize>(new_indent));
- dump(*i, true, indent_step, new_indent);
- o.write(",\n", 2);
- }
-
- // last element
- assert(not val.m_value.array->empty());
- o.write(indent_string.c_str(),
- static_cast<std::streamsize>(new_indent));
- dump(val.m_value.array->back(), true, indent_step,
- new_indent);
-
- o.put('\n');
- o.write(indent_string.c_str(),
- static_cast<std::streamsize>(current_indent));
- o.put(']');
- }
- else
- {
- o.put('[');
-
- // 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.put(',');
- }
-
- // last element
- assert(not val.m_value.array->empty());
- dump(val.m_value.array->back(), false, indent_step,
- current_indent);
-
- o.put(']');
- }
-
- return;
- }
-
- case value_t::string:
- {
- o.put('\"');
- dump_escaped(*val.m_value.string);
- o.put('\"');
- return;
- }
-
- case value_t::boolean:
- {
- if (val.m_value.boolean)
- {
- o.write("true", 4);
- }
- else
- {
- o.write("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;
- }
-
- case value_t::discarded:
- {
- o.write("<discarded>", 11);
- return;
- }
-
- case value_t::null:
- {
- o.write("null", 4);
- return;
- }
- }
- }
-
- private:
- /*!
- @brief calculates the extra space to escape a JSON string
-
- @param[in] s the string to escape
- @return the number of characters required to escape string @a s
-
- @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;
- }
-
- default:
- {
- return res;
- }
- }
- });
- }
-
- /*!
- @brief dump escaped 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. The escaped string is written to output stream @a o.
-
- @param[in] s the string to escape
-
- @complexity Linear in the length of string @a s.
- */
- void dump_escaped(const string_t &s) const
- {
- const auto space = extra_space(s);
- if (space == 0)
- {
- o.write(s.c_str(), static_cast<std::streamsize>(s.size()));
- return;
- }
-
- // create a result string of necessary size
- string_t result(s.size() + space, '\\');
- std::size_t pos = 0;
-
- for (const auto &c : s)
- {
- switch (c)
- {
- // quotation mark (0x22)
- case '"':
- {
- result[pos + 1] = '"';
- pos += 2;
- break;
- }
-
- // reverse solidus (0x5c)
- case '\\':
- {
- // nothing to change
- pos += 2;
- break;
- }
-
- // backspace (0x08)
- case '\b':
- {
- result[pos + 1] = 'b';
- pos += 2;
- break;
- }
-
- // formfeed (0x0c)
- case '\f':
- {
- result[pos + 1] = 'f';
- pos += 2;
- break;
- }
-
- // newline (0x0a)
- case '\n':
- {
- result[pos + 1] = 'n';
- pos += 2;
- break;
- }
-
- // carriage return (0x0d)
- case '\r':
- {
- result[pos + 1] = 'r';
- pos += 2;
- break;
- }
-
- // horizontal tab (0x09)
- case '\t':
- {
- result[pos + 1] = 't';
- pos += 2;
- break;
- }
-
- 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'};
-
- // print character c as \uxxxx
- for (const char m :
- {'u', '0', '0', hexify[c >> 4], hexify[c & 0x0f]})
- {
- result[++pos] = m;
- }
-
- ++pos;
- break;
- }
-
- default:
- {
- // all other characters are added as-is
- result[pos++] = c;
- break;
- }
- }
- }
-
- assert(pos == s.size() + space);
- o.write(result.c_str(),
- static_cast<std::streamsize>(result.size()));
- }
-
- /*!
- @brief dump an integer
-
- Dump a given integer to output stream @a o. Works internally with
- @a number_buffer.
-
- @param[in] x integer number (signed or unsigned) to dump
- @tparam NumberType either @a number_integer_t or @a number_unsigned_t
- */
- template <typename NumberType,
- detail::enable_if_t<
- std::is_same<NumberType, number_unsigned_t>::value or
- std::is_same<NumberType, number_integer_t>::value,
- int> = 0>
- void dump_integer(NumberType x)
- {
- // special case for "0"
- if (x == 0)
- {
- o.put('0');
- return;
- }
-
- const bool is_negative = x < 0;
- size_t i = 0;
-
- // spare 1 byte for '\0'
- while (x != 0 and i < number_buffer.size() - 1)
- {
- const auto digit = std::labs(static_cast<long>(x % 10));
- number_buffer[i++] = static_cast<char>('0' + digit);
- x /= 10;
- }
-
- // make sure the number has been processed completely
- assert(x == 0);
-
- if (is_negative)
- {
- // make sure there is capacity for the '-'
- assert(i < number_buffer.size() - 2);
- number_buffer[i++] = '-';
- }
-
- std::reverse(number_buffer.begin(), number_buffer.begin() + i);
- o.write(number_buffer.data(), static_cast<std::streamsize>(i));
- }
-
- /*!
- @brief dump a floating-point number
-
- Dump a given floating-point number to output stream @a o. Works
- internally with @a number_buffer.
-
- @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("null", 4);
- return;
- }
-
- // special case for 0.0 and -0.0
- if (x == 0)
- {
- if (std::signbit(x))
- {
- o.write("-0.0", 4);
- }
- else
- {
- o.write("0.0", 3);
- }
- return;
- }
-
- // get number of digits for a text -> float -> text round-trip
- static constexpr auto d =
- std::numeric_limits<number_float_t>::digits10;
-
- // the actual conversion
- std::ptrdiff_t len = snprintf(number_buffer.data(),
- number_buffer.size(), "%.*g", d, x);
-
- // negative value indicates an error
- assert(len > 0);
- // check if buffer was large enough
- assert(static_cast<size_t>(len) < number_buffer.size());
-
- // 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());
- }
-
- // convert decimal point to '.'
- if (decimal_point != '\0' and decimal_point != '.')
- {
- for (auto &c : number_buffer)
- {
- if (c == decimal_point)
- {
- c = '.';
- break;
- }
- }
- }
-
- o.write(number_buffer.data(), static_cast<std::streamsize>(len));
-
- // 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'; });
-
- if (value_is_int_like)
- {
- o.write(".0", 2);
- }
- }
-
- private:
- /// the output of the serializer
- std::ostream &o;
-
- /// a (hopefully) large enough character buffer
- std::array<char, 64> number_buffer{{}};
-
- /// 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';
-
- /// the indentation string
- string_t indent_string = string_t(512, ' ');
- };
-
-public:
- /*!
- @brief serialize to stream
-
- 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)`.
-
- @param[in,out] o stream to serialize to
- @param[in] j JSON value to serialize
-
- @return the stream @a o
-
- @complexity Linear.
-
- @liveexample{The example below shows the serialization with different
- parameters to `width` to adjust the indentation level.,operator_serialize}
-
- @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);
-
- // reset width to 0 for subsequent calls to this stream
- o.width(0);
-
- // do the actual serialization
- serializer s(o);
- s.dump(j, pretty_print, static_cast<unsigned int>(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;
- }
-
- /// @}
-
- /////////////////////
- // deserialization //
- /////////////////////
-
- /// @name deserialization
- /// @{
-
- /*!
- @brief deserialize from an array
-
- This function reads from an array of 1-byte values.
-
- @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.**
-
- @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.
-
- @liveexample{The example below demonstrates the `parse()` function reading
- from an array.,parse__array__parser_callback_t}
-
- @since version 2.0.3
- */
- template <class T, std::size_t N>
- 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);
- }
-
- /*!
- @brief deserialize from string literal
-
- @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 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.
- @note String containers like `std::string` or @ref string_t can be parsed
- with @ref parse(const ContiguousContainer&, const parser_callback_t)
-
- @liveexample{The example below demonstrates the `parse()` function with
- and without callback function.,parse__string__parser_callback_t}
-
- @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 <typename CharT,
- typename std::enable_if<
- std::is_pointer<CharT>::value and
- std::is_integral<
- typename std::remove_pointer<CharT>::type>::value and
- sizeof(typename std::remove_pointer<CharT>::type) == 1,
- int>::type = 0>
- static basic_json parse(const CharT s, const parser_callback_t cb = nullptr)
- {
- return parser(reinterpret_cast<const char *>(s), cb).parse();
- }
-
- /*!
- @brief deserialize from stream
-
- @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)
-
- @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
- @throw parse_error.111 if input stream is in a bad state
-
- @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
- */
- static basic_json parse(std::istream &i,
- const parser_callback_t cb = nullptr)
- {
- return parser(i, cb).parse();
- }
-
- /*!
- @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();
- }
-
- /*!
- @brief deserialize from an iterator range with contiguous storage
-
- 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.
-
- @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.**
-
- @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.
-
- @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)
-
- @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
- */
- template <class IteratorType,
- typename std::enable_if<
- std::is_base_of<std::random_access_iterator_tag,
- typename std::iterator_traits<
- IteratorType>::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::pair<bool, int>(true, 0),
- [&first](std::pair<bool, int> 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<IteratorType>::value_type) ==
- 1,
- "each element in the iterator range must have the size of 1 byte");
-
- // 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();
- }
-
- return parser(first, last, cb).parse();
- }
-
- /*!
- @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.**
-
- @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.
-
- @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)
-
- @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 a contiguous container.,parse__contiguouscontainer__parser_callback_t}
-
- @since version 2.0.3
- */
- template <class ContiguousContainer,
- typename std::enable_if<
- not std::is_pointer<ContiguousContainer>::value and
- std::is_base_of<
- std::random_access_iterator_tag,
- typename std::iterator_traits<decltype(std::begin(
- std::declval<ContiguousContainer const>()))>::
- 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);
- }
-
- /*!
- @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;`.
- */
- JSON_DEPRECATED
- friend std::istream &operator<<(basic_json &j, std::istream &i)
- {
- j = parser(i).parse();
- return i;
- }
-
- /*!
- @brief deserialize from stream
-
- Deserializes an input stream to a JSON value.
-
- @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
-
- @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
-
- @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 std::istream &operator>>(std::istream &i, basic_json &j)
- {
- j = parser(i).parse();
- return i;
- }
-
- /// @}
-
- //////////////////////////////////////////
- // binary serialization/deserialization //
- //////////////////////////////////////////
-
- /// @name binary serialization/deserialization support
- /// @{
-
-private:
- /*!
- @note Some code in the switch cases has been copied, because otherwise
- copilers would complain about implicit fallthrough and there is no
- portable attribute to mute such warnings.
- */
- template <typename T>
- static void add_to_vector(std::vector<uint8_t> &vec, size_t bytes,
- const T number)
- {
- assert(bytes == 1 or bytes == 2 or bytes == 4 or bytes == 8);
-
- switch (bytes)
- {
- case 8:
- {
- vec.push_back(static_cast<uint8_t>(
- (static_cast<uint64_t>(number) >> 070) & 0xff));
- vec.push_back(static_cast<uint8_t>(
- (static_cast<uint64_t>(number) >> 060) & 0xff));
- vec.push_back(static_cast<uint8_t>(
- (static_cast<uint64_t>(number) >> 050) & 0xff));
- vec.push_back(static_cast<uint8_t>(
- (static_cast<uint64_t>(number) >> 040) & 0xff));
- vec.push_back(static_cast<uint8_t>((number >> 030) & 0xff));
- vec.push_back(static_cast<uint8_t>((number >> 020) & 0xff));
- vec.push_back(static_cast<uint8_t>((number >> 010) & 0xff));
- vec.push_back(static_cast<uint8_t>(number & 0xff));
- break;
- }
-
- case 4:
- {
- vec.push_back(static_cast<uint8_t>((number >> 030) & 0xff));
- vec.push_back(static_cast<uint8_t>((number >> 020) & 0xff));
- vec.push_back(static_cast<uint8_t>((number >> 010) & 0xff));
- vec.push_back(static_cast<uint8_t>(number & 0xff));
- break;
- }
-
- case 2:
- {
- vec.push_back(static_cast<uint8_t>((number >> 010) & 0xff));
- vec.push_back(static_cast<uint8_t>(number & 0xff));
- break;
- }
-
- case 1:
- {
- vec.push_back(static_cast<uint8_t>(number & 0xff));
- break;
- }
- }
- }
-
- /*!
- @brief take sufficient bytes from a vector to fill an integer variable
-
- In the context of binary serialization formats, we need to read several
- bytes from a byte vector and combine them to multi-byte integral data
- types.
-
- @param[in] vec byte vector to read from
- @param[in] current_index the position in the vector after which to read
-
- @return the next sizeof(T) bytes from @a vec, in reverse order as T
-
- @tparam T the integral return type
-
- @throw parse_error.110 if there are less than sizeof(T)+1 bytes in the
- vector @a vec to read
-
- In the for loop, the bytes from the vector are copied in reverse order into
- the return value. In the figures below, let sizeof(T)=4 and `i` be the loop
- variable.
-
- Precondition:
-
- vec: | | | a | b | c | d | T: | | | | |
- ^ ^ ^ ^
- current_index i ptr sizeof(T)
-
- Postcondition:
-
- vec: | | | a | b | c | d | T: | d | c | b | a |
- ^ ^ ^
- | i ptr
- current_index
-
- @sa Code adapted from <http://stackoverflow.com/a/41031865/266378>.
- */
- template <typename T>
- static T get_from_vector(const std::vector<uint8_t> &vec,
- const size_t current_index)
- {
- // check if we can read sizeof(T) bytes starting the next index
- check_length(vec.size(), sizeof(T), current_index + 1);
-
- T result;
- auto *ptr = reinterpret_cast<uint8_t *>(&result);
- for (size_t i = 0; i < sizeof(T); ++i)
- {
- *ptr++ = vec[current_index + sizeof(T) - i];
- }
- return result;
- }
-
- /*!
- @brief create a MessagePack serialization of a given JSON value
-
- This is a straightforward implementation of the MessagePack specification.
-
- @param[in] j JSON value to serialize
- @param[in,out] v byte vector to write the serialization to
-
- @sa https://github.com/msgpack/msgpack/blob/master/spec.md
- */
- static void to_msgpack_internal(const basic_json &j,
- std::vector<uint8_t> &v)
- {
- switch (j.type())
- {
- case value_t::null:
- {
- // nil
- v.push_back(0xc0);
- break;
- }
-
- case value_t::boolean:
- {
- // true and false
- v.push_back(j.m_value.boolean ? 0xc3 : 0xc2);
- break;
- }
-
- case value_t::number_integer:
- {
- 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
- add_to_vector(v, 1, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <=
- (std::numeric_limits<uint8_t>::max)())
- {
- // uint 8
- v.push_back(0xcc);
- add_to_vector(v, 1, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <=
- (std::numeric_limits<uint16_t>::max)())
- {
- // uint 16
- v.push_back(0xcd);
- add_to_vector(v, 2, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <=
- (std::numeric_limits<uint32_t>::max)())
- {
- // uint 32
- v.push_back(0xce);
- add_to_vector(v, 4, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <=
- (std::numeric_limits<uint64_t>::max)())
- {
- // uint 64
- v.push_back(0xcf);
- add_to_vector(v, 8, j.m_value.number_unsigned);
- }
- }
- else
- {
- if (j.m_value.number_integer >= -32)
- {
- // negative fixnum
- add_to_vector(v, 1, j.m_value.number_integer);
- }
- else if (j.m_value.number_integer >=
- (std::numeric_limits<int8_t>::min)() and
- j.m_value.number_integer <=
- (std::numeric_limits<int8_t>::max)())
- {
- // int 8
- v.push_back(0xd0);
- add_to_vector(v, 1, j.m_value.number_integer);
- }
- else if (j.m_value.number_integer >=
- (std::numeric_limits<int16_t>::min)() and
- j.m_value.number_integer <=
- (std::numeric_limits<int16_t>::max)())
- {
- // int 16
- v.push_back(0xd1);
- add_to_vector(v, 2, j.m_value.number_integer);
- }
- else if (j.m_value.number_integer >=
- (std::numeric_limits<int32_t>::min)() and
- j.m_value.number_integer <=
- (std::numeric_limits<int32_t>::max)())
- {
- // int 32
- v.push_back(0xd2);
- add_to_vector(v, 4, j.m_value.number_integer);
- }
- else if (j.m_value.number_integer >=
- (std::numeric_limits<int64_t>::min)() and
- j.m_value.number_integer <=
- (std::numeric_limits<int64_t>::max)())
- {
- // int 64
- v.push_back(0xd3);
- add_to_vector(v, 8, j.m_value.number_integer);
- }
- }
- break;
- }
-
- case value_t::number_unsigned:
- {
- if (j.m_value.number_unsigned < 128)
- {
- // positive fixnum
- add_to_vector(v, 1, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <=
- (std::numeric_limits<uint8_t>::max)())
- {
- // uint 8
- v.push_back(0xcc);
- add_to_vector(v, 1, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <=
- (std::numeric_limits<uint16_t>::max)())
- {
- // uint 16
- v.push_back(0xcd);
- add_to_vector(v, 2, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <=
- (std::numeric_limits<uint32_t>::max)())
- {
- // uint 32
- v.push_back(0xce);
- add_to_vector(v, 4, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <=
- (std::numeric_limits<uint64_t>::max)())
- {
- // uint 64
- v.push_back(0xcf);
- add_to_vector(v, 8, j.m_value.number_unsigned);
- }
- break;
- }
-
- case value_t::number_float:
- {
- // float 64
- v.push_back(0xcb);
- const auto *helper =
- reinterpret_cast<const uint8_t *>(&(j.m_value.number_float));
- for (size_t i = 0; i < 8; ++i)
- {
- v.push_back(helper[7 - i]);
- }
- break;
- }
-
- case value_t::string:
- {
- const auto N = j.m_value.string->size();
- if (N <= 31)
- {
- // fixstr
- v.push_back(static_cast<uint8_t>(0xa0 | N));
- }
- else if (N <= 255)
- {
- // str 8
- v.push_back(0xd9);
- add_to_vector(v, 1, N);
- }
- else if (N <= 65535)
- {
- // str 16
- v.push_back(0xda);
- add_to_vector(v, 2, N);
- }
- else if (N <= 4294967295)
- {
- // str 32
- v.push_back(0xdb);
- add_to_vector(v, 4, N);
- }
-
- // append string
- std::copy(j.m_value.string->begin(), j.m_value.string->end(),
- std::back_inserter(v));
- break;
- }
-
- case value_t::array:
- {
- const auto N = j.m_value.array->size();
- if (N <= 15)
- {
- // fixarray
- v.push_back(static_cast<uint8_t>(0x90 | N));
- }
- else if (N <= 0xffff)
- {
- // array 16
- v.push_back(0xdc);
- add_to_vector(v, 2, N);
- }
- else if (N <= 0xffffffff)
- {
- // array 32
- v.push_back(0xdd);
- add_to_vector(v, 4, N);
- }
-
- // append each element
- for (const auto &el : *j.m_value.array)
- {
- to_msgpack_internal(el, v);
- }
- break;
- }
-
- case value_t::object:
- {
- const auto N = j.m_value.object->size();
- if (N <= 15)
- {
- // fixmap
- v.push_back(static_cast<uint8_t>(0x80 | (N & 0xf)));
- }
- else if (N <= 65535)
- {
- // map 16
- v.push_back(0xde);
- add_to_vector(v, 2, N);
- }
- else if (N <= 4294967295)
- {
- // map 32
- v.push_back(0xdf);
- add_to_vector(v, 4, N);
- }
-
- // append each element
- for (const auto &el : *j.m_value.object)
- {
- to_msgpack_internal(el.first, v);
- to_msgpack_internal(el.second, v);
- }
- break;
- }
-
- default:
- {
- break;
- }
- }
- }
-
- /*!
- @brief create a CBOR serialization of a given JSON value
-
- This is a straightforward implementation of the CBOR specification.
-
- @param[in] j JSON value to serialize
- @param[in,out] v byte vector to write the serialization to
-
- @sa https://tools.ietf.org/html/rfc7049
- */
- static void to_cbor_internal(const basic_json &j, std::vector<uint8_t> &v)
- {
- switch (j.type())
- {
- case value_t::null:
- {
- v.push_back(0xf6);
- break;
- }
-
- case value_t::boolean:
- {
- v.push_back(j.m_value.boolean ? 0xf5 : 0xf4);
- break;
- }
-
- case value_t::number_integer:
- {
- 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)
- {
- add_to_vector(v, 1, j.m_value.number_integer);
- }
- else if (j.m_value.number_integer <=
- (std::numeric_limits<uint8_t>::max)())
- {
- v.push_back(0x18);
- // one-byte uint8_t
- add_to_vector(v, 1, j.m_value.number_integer);
- }
- else if (j.m_value.number_integer <=
- (std::numeric_limits<uint16_t>::max)())
- {
- v.push_back(0x19);
- // two-byte uint16_t
- add_to_vector(v, 2, j.m_value.number_integer);
- }
- else if (j.m_value.number_integer <=
- (std::numeric_limits<uint32_t>::max)())
- {
- v.push_back(0x1a);
- // four-byte uint32_t
- add_to_vector(v, 4, j.m_value.number_integer);
- }
- else
- {
- v.push_back(0x1b);
- // eight-byte uint64_t
- add_to_vector(v, 8, 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)
- {
- v.push_back(static_cast<uint8_t>(0x20 + positive_number));
- }
- else if (positive_number <=
- (std::numeric_limits<uint8_t>::max)())
- {
- // int 8
- v.push_back(0x38);
- add_to_vector(v, 1, positive_number);
- }
- else if (positive_number <=
- (std::numeric_limits<uint16_t>::max)())
- {
- // int 16
- v.push_back(0x39);
- add_to_vector(v, 2, positive_number);
- }
- else if (positive_number <=
- (std::numeric_limits<uint32_t>::max)())
- {
- // int 32
- v.push_back(0x3a);
- add_to_vector(v, 4, positive_number);
- }
- else
- {
- // int 64
- v.push_back(0x3b);
- add_to_vector(v, 8, positive_number);
- }
- }
- break;
- }
-
- case value_t::number_unsigned:
- {
- if (j.m_value.number_unsigned <= 0x17)
- {
- v.push_back(static_cast<uint8_t>(j.m_value.number_unsigned));
- }
- else if (j.m_value.number_unsigned <= 0xff)
- {
- v.push_back(0x18);
- // one-byte uint8_t
- add_to_vector(v, 1, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <= 0xffff)
- {
- v.push_back(0x19);
- // two-byte uint16_t
- add_to_vector(v, 2, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <= 0xffffffff)
- {
- v.push_back(0x1a);
- // four-byte uint32_t
- add_to_vector(v, 4, j.m_value.number_unsigned);
- }
- else if (j.m_value.number_unsigned <= 0xffffffffffffffff)
- {
- v.push_back(0x1b);
- // eight-byte uint64_t
- add_to_vector(v, 8, j.m_value.number_unsigned);
- }
- break;
- }
-
- case value_t::number_float:
- {
- // Double-Precision Float
- v.push_back(0xfb);
- const auto *helper =
- reinterpret_cast<const uint8_t *>(&(j.m_value.number_float));
- for (size_t i = 0; i < 8; ++i)
- {
- v.push_back(helper[7 - i]);
- }
- break;
- }
-
- case value_t::string:
- {
- const auto N = j.m_value.string->size();
- if (N <= 0x17)
- {
- v.push_back(
- static_cast<uint8_t>(0x60 + N)); // 1 byte for string + size
- }
- else if (N <= 0xff)
- {
- v.push_back(0x78); // one-byte uint8_t for N
- add_to_vector(v, 1, N);
- }
- else if (N <= 0xffff)
- {
- v.push_back(0x79); // two-byte uint16_t for N
- add_to_vector(v, 2, N);
- }
- else if (N <= 0xffffffff)
- {
- v.push_back(0x7a); // four-byte uint32_t for N
- add_to_vector(v, 4, N);
- }
- // LCOV_EXCL_START
- else if (N <= 0xffffffffffffffff)
- {
- v.push_back(0x7b); // eight-byte uint64_t for N
- add_to_vector(v, 8, N);
- }
- // LCOV_EXCL_STOP
-
- // append string
- std::copy(j.m_value.string->begin(), j.m_value.string->end(),
- std::back_inserter(v));
- break;
- }
-
- case value_t::array:
- {
- const auto N = j.m_value.array->size();
- if (N <= 0x17)
- {
- v.push_back(
- static_cast<uint8_t>(0x80 + N)); // 1 byte for array + size
- }
- else if (N <= 0xff)
- {
- v.push_back(0x98); // one-byte uint8_t for N
- add_to_vector(v, 1, N);
- }
- else if (N <= 0xffff)
- {
- v.push_back(0x99); // two-byte uint16_t for N
- add_to_vector(v, 2, N);
- }
- else if (N <= 0xffffffff)
- {
- v.push_back(0x9a); // four-byte uint32_t for N
- add_to_vector(v, 4, N);
- }
- // LCOV_EXCL_START
- else if (N <= 0xffffffffffffffff)
- {
- v.push_back(0x9b); // eight-byte uint64_t for N
- add_to_vector(v, 8, N);
- }
- // LCOV_EXCL_STOP
-
- // append each element
- for (const auto &el : *j.m_value.array)
- {
- to_cbor_internal(el, v);
- }
- break;
- }
-
- case value_t::object:
- {
- const auto N = j.m_value.object->size();
- if (N <= 0x17)
- {
- v.push_back(
- static_cast<uint8_t>(0xa0 + N)); // 1 byte for object + size
- }
- else if (N <= 0xff)
- {
- v.push_back(0xb8);
- add_to_vector(v, 1, N); // one-byte uint8_t for N
- }
- else if (N <= 0xffff)
- {
- v.push_back(0xb9);
- add_to_vector(v, 2, N); // two-byte uint16_t for N
- }
- else if (N <= 0xffffffff)
- {
- v.push_back(0xba);
- add_to_vector(v, 4, N); // four-byte uint32_t for N
- }
- // LCOV_EXCL_START
- else if (N <= 0xffffffffffffffff)
- {
- v.push_back(0xbb);
- add_to_vector(v, 8, N); // eight-byte uint64_t for N
- }
- // LCOV_EXCL_STOP
-
- // append each element
- for (const auto &el : *j.m_value.object)
- {
- to_cbor_internal(el.first, v);
- to_cbor_internal(el.second, v);
- }
- break;
- }
-
- default:
- {
- break;
- }
- }
- }
-
- /*
- @brief checks if given lengths do not exceed the size of a given vector
-
- To secure the access to the byte vector during CBOR/MessagePack
- deserialization, bytes are copied from the vector into buffers. This
- function checks if the number of bytes to copy (@a len) does not exceed
- the size @s size of the vector. Additionally, an @a offset is given from
- where to start reading the bytes.
-
- This function checks whether reading the bytes is safe; that is, offset is
- a valid index in the vector, offset+len
-
- @param[in] size size of the byte vector
- @param[in] len number of bytes to read
- @param[in] offset offset where to start reading
-
- vec: x x x x x X X X X X
- ^ ^ ^
- 0 offset len
-
- @throws out_of_range if `len > v.size()`
- */
- static void check_length(const size_t size, const size_t len,
- const size_t offset)
- {
- // simple case: requested length is greater than the vector's length
- if (len > size or offset > size)
- {
- JSON_THROW(parse_error::create(
- 110, offset + 1,
- "cannot read " + std::to_string(len) + " bytes from vector"));
- }
-
- // second case: adding offset would result in overflow
- if ((size > ((std::numeric_limits<size_t>::max)() - offset)))
- {
- JSON_THROW(parse_error::create(
- 110, offset + 1,
- "cannot read " + std::to_string(len) + " bytes from vector"));
- }
-
- // last case: reading past the end of the vector
- if (len + offset > size)
- {
- JSON_THROW(parse_error::create(
- 110, offset + 1,
- "cannot read " + std::to_string(len) + " bytes from vector"));
- }
- }
-
- /*!
- @brief check if the next byte belongs to a string
-
- While parsing a map, the keys must be strings. This function checks if the
- current byte is one of the start bytes for a string in MessagePack:
-
- - 0xa0 - 0xbf: fixstr
- - 0xd9: str 8
- - 0xda: str 16
- - 0xdb: str 32
-
- @param[in] v MessagePack serialization
- @param[in] idx byte index in @a v to check for a string
-
- @throw parse_error.113 if `v[idx]` does not belong to a string
- */
- static void msgpack_expect_string(const std::vector<uint8_t> &v, size_t idx)
- {
- check_length(v.size(), 1, idx);
-
- const auto byte = v[idx];
- if ((byte >= 0xa0 and byte <= 0xbf) or (byte >= 0xd9 and byte <= 0xdb))
- {
- return;
- }
-
- std::stringstream ss;
- ss << std::hex << static_cast<int>(v[idx]);
- JSON_THROW(parse_error::create(
- 113, idx + 1,
- "expected a MessagePack string; last byte: 0x" + ss.str()));
- }
-
- /*!
- @brief check if the next byte belongs to a string
-
- While parsing a map, the keys must be strings. This function checks if the
- current byte is one of the start bytes for a string in CBOR:
-
- - 0x60 - 0x77: fixed length
- - 0x78 - 0x7b: variable length
- - 0x7f: indefinity length
-
- @param[in] v CBOR serialization
- @param[in] idx byte index in @a v to check for a string
-
- @throw parse_error.113 if `v[idx]` does not belong to a string
- */
- static void cbor_expect_string(const std::vector<uint8_t> &v, size_t idx)
- {
- check_length(v.size(), 1, idx);
-
- const auto byte = v[idx];
- if ((byte >= 0x60 and byte <= 0x7b) or byte == 0x7f)
- {
- return;
- }
-
- std::stringstream ss;
- ss << std::hex << static_cast<int>(v[idx]);
- JSON_THROW(parse_error::create(
- 113, idx + 1, "expected a CBOR string; last byte: 0x" + ss.str()));
- }
-
- /*!
- @brief create a JSON value from a given MessagePack vector
-
- @param[in] v MessagePack serialization
- @param[in] idx byte index to start reading from @a v
-
- @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
-
- @sa https://github.com/msgpack/msgpack/blob/master/spec.md
- */
- static basic_json from_msgpack_internal(const std::vector<uint8_t> &v,
- size_t &idx)
- {
- // store and increment index
- const size_t current_idx = idx++;
-
- // make sure reading 1 byte is safe
- check_length(v.size(), 1, current_idx);
-
- if (v[current_idx] <= 0xbf)
- {
- if (v[current_idx] <= 0x7f) // positive fixint
- {
- return v[current_idx];
- }
- if (v[current_idx] <= 0x8f) // fixmap
- {
- basic_json result = value_t::object;
- const size_t len = v[current_idx] & 0x0f;
- for (size_t i = 0; i < len; ++i)
- {
- msgpack_expect_string(v, idx);
- std::string key = from_msgpack_internal(v, idx);
- result[key] = from_msgpack_internal(v, idx);
- }
- return result;
- }
- else if (v[current_idx] <= 0x9f) // fixarray
- {
- basic_json result = value_t::array;
- const size_t len = v[current_idx] & 0x0f;
- for (size_t i = 0; i < len; ++i)
- {
- result.push_back(from_msgpack_internal(v, idx));
- }
- return result;
- }
- else // fixstr
- {
- const size_t len = v[current_idx] & 0x1f;
- const size_t offset = current_idx + 1;
- idx += len; // skip content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
- }
- else if (v[current_idx] >= 0xe0) // negative fixint
- {
- return static_cast<int8_t>(v[current_idx]);
- }
- else
- {
- switch (v[current_idx])
- {
- case 0xc0: // nil
- {
- return value_t::null;
- }
-
- case 0xc2: // false
- {
- return false;
- }
-
- case 0xc3: // true
- {
- return true;
- }
-
- case 0xca: // float 32
- {
- // copy bytes in reverse order into the double variable
- float res;
- check_length(v.size(), sizeof(float), current_idx + 1);
- for (size_t byte = 0; byte < sizeof(float); ++byte)
- {
- reinterpret_cast<uint8_t *>(
- &res)[sizeof(float) - byte - 1] =
- v[current_idx + 1 + byte];
- }
- idx += sizeof(float); // skip content bytes
- return res;
- }
-
- case 0xcb: // float 64
- {
- // copy bytes in reverse order into the double variable
- double res;
- check_length(v.size(), sizeof(double), current_idx + 1);
- for (size_t byte = 0; byte < sizeof(double); ++byte)
- {
- reinterpret_cast<uint8_t *>(
- &res)[sizeof(double) - byte - 1] =
- v[current_idx + 1 + byte];
- }
- idx += sizeof(double); // skip content bytes
- return res;
- }
-
- case 0xcc: // uint 8
- {
- idx += 1; // skip content byte
- return get_from_vector<uint8_t>(v, current_idx);
- }
-
- case 0xcd: // uint 16
- {
- idx += 2; // skip 2 content bytes
- return get_from_vector<uint16_t>(v, current_idx);
- }
-
- case 0xce: // uint 32
- {
- idx += 4; // skip 4 content bytes
- return get_from_vector<uint32_t>(v, current_idx);
- }
-
- case 0xcf: // uint 64
- {
- idx += 8; // skip 8 content bytes
- return get_from_vector<uint64_t>(v, current_idx);
- }
-
- case 0xd0: // int 8
- {
- idx += 1; // skip content byte
- return get_from_vector<int8_t>(v, current_idx);
- }
-
- case 0xd1: // int 16
- {
- idx += 2; // skip 2 content bytes
- return get_from_vector<int16_t>(v, current_idx);
- }
-
- case 0xd2: // int 32
- {
- idx += 4; // skip 4 content bytes
- return get_from_vector<int32_t>(v, current_idx);
- }
-
- case 0xd3: // int 64
- {
- idx += 8; // skip 8 content bytes
- return get_from_vector<int64_t>(v, current_idx);
- }
-
- case 0xd9: // str 8
- {
- const auto len = static_cast<size_t>(
- get_from_vector<uint8_t>(v, current_idx));
- const size_t offset = current_idx + 2;
- idx += len + 1; // skip size byte + content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
-
- case 0xda: // str 16
- {
- const auto len = static_cast<size_t>(
- get_from_vector<uint16_t>(v, current_idx));
- const size_t offset = current_idx + 3;
- idx += len + 2; // skip 2 size bytes + content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
-
- case 0xdb: // str 32
- {
- const auto len = static_cast<size_t>(
- get_from_vector<uint32_t>(v, current_idx));
- const size_t offset = current_idx + 5;
- idx += len + 4; // skip 4 size bytes + content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
-
- case 0xdc: // array 16
- {
- basic_json result = value_t::array;
- const auto len = static_cast<size_t>(
- get_from_vector<uint16_t>(v, current_idx));
- idx += 2; // skip 2 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- result.push_back(from_msgpack_internal(v, idx));
- }
- return result;
- }
-
- case 0xdd: // array 32
- {
- basic_json result = value_t::array;
- const auto len = static_cast<size_t>(
- get_from_vector<uint32_t>(v, current_idx));
- idx += 4; // skip 4 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- result.push_back(from_msgpack_internal(v, idx));
- }
- return result;
- }
-
- case 0xde: // map 16
- {
- basic_json result = value_t::object;
- const auto len = static_cast<size_t>(
- get_from_vector<uint16_t>(v, current_idx));
- idx += 2; // skip 2 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- msgpack_expect_string(v, idx);
- std::string key = from_msgpack_internal(v, idx);
- result[key] = from_msgpack_internal(v, idx);
- }
- return result;
- }
-
- case 0xdf: // map 32
- {
- basic_json result = value_t::object;
- const auto len = static_cast<size_t>(
- get_from_vector<uint32_t>(v, current_idx));
- idx += 4; // skip 4 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- msgpack_expect_string(v, idx);
- std::string key = from_msgpack_internal(v, idx);
- result[key] = from_msgpack_internal(v, idx);
- }
- return result;
- }
-
- default:
- {
- std::stringstream ss;
- ss << std::hex << static_cast<int>(v[current_idx]);
- JSON_THROW(parse_error::create(
- 112, current_idx + 1,
- "error reading MessagePack; last byte: 0x" + ss.str()));
- }
- }
- }
- }
-
- /*!
- @brief create a JSON value from a given CBOR vector
-
- @param[in] v CBOR serialization
- @param[in] idx byte index to start reading from @a v
-
- @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
-
- @sa https://tools.ietf.org/html/rfc7049
- */
- static basic_json from_cbor_internal(const std::vector<uint8_t> &v,
- size_t &idx)
- {
- // store and increment index
- const size_t current_idx = idx++;
-
- // make sure reading 1 byte is safe
- check_length(v.size(), 1, current_idx);
-
- switch (v[current_idx])
- {
- // 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:
- {
- return v[current_idx];
- }
-
- case 0x18: // Unsigned integer (one-byte uint8_t follows)
- {
- idx += 1; // skip content byte
- return get_from_vector<uint8_t>(v, current_idx);
- }
-
- case 0x19: // Unsigned integer (two-byte uint16_t follows)
- {
- idx += 2; // skip 2 content bytes
- return get_from_vector<uint16_t>(v, current_idx);
- }
-
- case 0x1a: // Unsigned integer (four-byte uint32_t follows)
- {
- idx += 4; // skip 4 content bytes
- return get_from_vector<uint32_t>(v, current_idx);
- }
-
- case 0x1b: // Unsigned integer (eight-byte uint64_t follows)
- {
- idx += 8; // skip 8 content bytes
- return get_from_vector<uint64_t>(v, current_idx);
- }
-
- // 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<int8_t>(0x20 - 1 - v[current_idx]);
- }
-
- case 0x38: // Negative integer (one-byte uint8_t follows)
- {
- idx += 1; // skip content byte
- // must be uint8_t !
- return static_cast<number_integer_t>(-1) -
- get_from_vector<uint8_t>(v, current_idx);
- }
-
- case 0x39: // Negative integer -1-n (two-byte uint16_t follows)
- {
- idx += 2; // skip 2 content bytes
- return static_cast<number_integer_t>(-1) -
- get_from_vector<uint16_t>(v, current_idx);
- }
-
- case 0x3a: // Negative integer -1-n (four-byte uint32_t follows)
- {
- idx += 4; // skip 4 content bytes
- return static_cast<number_integer_t>(-1) -
- get_from_vector<uint32_t>(v, current_idx);
- }
-
- case 0x3b: // Negative integer -1-n (eight-byte uint64_t follows)
- {
- idx += 8; // skip 8 content bytes
- return static_cast<number_integer_t>(-1) -
- static_cast<number_integer_t>(
- get_from_vector<uint64_t>(v, current_idx));
- }
-
- // 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:
- {
- const auto len = static_cast<size_t>(v[current_idx] - 0x60);
- const size_t offset = current_idx + 1;
- idx += len; // skip content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
-
- case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
- {
- const auto len =
- static_cast<size_t>(get_from_vector<uint8_t>(v, current_idx));
- const size_t offset = current_idx + 2;
- idx += len + 1; // skip size byte + content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
-
- case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
- {
- const auto len =
- static_cast<size_t>(get_from_vector<uint16_t>(v, current_idx));
- const size_t offset = current_idx + 3;
- idx += len + 2; // skip 2 size bytes + content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
-
- case 0x7a: // UTF-8 string (four-byte uint32_t for n follow)
- {
- const auto len =
- static_cast<size_t>(get_from_vector<uint32_t>(v, current_idx));
- const size_t offset = current_idx + 5;
- idx += len + 4; // skip 4 size bytes + content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
-
- case 0x7b: // UTF-8 string (eight-byte uint64_t for n follow)
- {
- const auto len =
- static_cast<size_t>(get_from_vector<uint64_t>(v, current_idx));
- const size_t offset = current_idx + 9;
- idx += len + 8; // skip 8 size bytes + content bytes
- check_length(v.size(), len, offset);
- return std::string(
- reinterpret_cast<const char *>(v.data()) + offset, len);
- }
-
- case 0x7f: // UTF-8 string (indefinite length)
- {
- std::string result;
- while (static_cast<void>(check_length(v.size(), 1, idx)),
- v[idx] != 0xff)
- {
- string_t s = from_cbor_internal(v, idx);
- result += s;
- }
- // skip break byte (0xFF)
- idx += 1;
- return result;
- }
-
- // 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<size_t>(v[current_idx] - 0x80);
- for (size_t i = 0; i < len; ++i)
- {
- result.push_back(from_cbor_internal(v, idx));
- }
- return result;
- }
-
- case 0x98: // array (one-byte uint8_t for n follows)
- {
- basic_json result = value_t::array;
- const auto len =
- static_cast<size_t>(get_from_vector<uint8_t>(v, current_idx));
- idx += 1; // skip 1 size byte
- for (size_t i = 0; i < len; ++i)
- {
- result.push_back(from_cbor_internal(v, idx));
- }
- return result;
- }
-
- case 0x99: // array (two-byte uint16_t for n follow)
- {
- basic_json result = value_t::array;
- const auto len =
- static_cast<size_t>(get_from_vector<uint16_t>(v, current_idx));
- idx += 2; // skip 4 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- result.push_back(from_cbor_internal(v, idx));
- }
- return result;
- }
-
- case 0x9a: // array (four-byte uint32_t for n follow)
- {
- basic_json result = value_t::array;
- const auto len =
- static_cast<size_t>(get_from_vector<uint32_t>(v, current_idx));
- idx += 4; // skip 4 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- result.push_back(from_cbor_internal(v, idx));
- }
- return result;
- }
-
- case 0x9b: // array (eight-byte uint64_t for n follow)
- {
- basic_json result = value_t::array;
- const auto len =
- static_cast<size_t>(get_from_vector<uint64_t>(v, current_idx));
- idx += 8; // skip 8 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- result.push_back(from_cbor_internal(v, idx));
- }
- return result;
- }
-
- case 0x9f: // array (indefinite length)
- {
- basic_json result = value_t::array;
- while (static_cast<void>(check_length(v.size(), 1, idx)),
- v[idx] != 0xff)
- {
- result.push_back(from_cbor_internal(v, idx));
- }
- // skip break byte (0xFF)
- idx += 1;
- return result;
- }
-
- // 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<size_t>(v[current_idx] - 0xa0);
- for (size_t i = 0; i < len; ++i)
- {
- cbor_expect_string(v, idx);
- std::string key = from_cbor_internal(v, idx);
- result[key] = from_cbor_internal(v, idx);
- }
- return result;
- }
-
- case 0xb8: // map (one-byte uint8_t for n follows)
- {
- basic_json result = value_t::object;
- const auto len =
- static_cast<size_t>(get_from_vector<uint8_t>(v, current_idx));
- idx += 1; // skip 1 size byte
- for (size_t i = 0; i < len; ++i)
- {
- cbor_expect_string(v, idx);
- std::string key = from_cbor_internal(v, idx);
- result[key] = from_cbor_internal(v, idx);
- }
- return result;
- }
-
- case 0xb9: // map (two-byte uint16_t for n follow)
- {
- basic_json result = value_t::object;
- const auto len =
- static_cast<size_t>(get_from_vector<uint16_t>(v, current_idx));
- idx += 2; // skip 2 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- cbor_expect_string(v, idx);
- std::string key = from_cbor_internal(v, idx);
- result[key] = from_cbor_internal(v, idx);
- }
- return result;
- }
-
- case 0xba: // map (four-byte uint32_t for n follow)
- {
- basic_json result = value_t::object;
- const auto len =
- static_cast<size_t>(get_from_vector<uint32_t>(v, current_idx));
- idx += 4; // skip 4 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- cbor_expect_string(v, idx);
- std::string key = from_cbor_internal(v, idx);
- result[key] = from_cbor_internal(v, idx);
- }
- return result;
- }
-
- case 0xbb: // map (eight-byte uint64_t for n follow)
- {
- basic_json result = value_t::object;
- const auto len =
- static_cast<size_t>(get_from_vector<uint64_t>(v, current_idx));
- idx += 8; // skip 8 size bytes
- for (size_t i = 0; i < len; ++i)
- {
- cbor_expect_string(v, idx);
- std::string key = from_cbor_internal(v, idx);
- result[key] = from_cbor_internal(v, idx);
- }
- return result;
- }
-
- case 0xbf: // map (indefinite length)
- {
- basic_json result = value_t::object;
- while (static_cast<void>(check_length(v.size(), 1, idx)),
- v[idx] != 0xff)
- {
- cbor_expect_string(v, idx);
- std::string key = from_cbor_internal(v, idx);
- result[key] = from_cbor_internal(v, idx);
- }
- // skip break byte (0xFF)
- idx += 1;
- 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)
- {
- idx += 2; // skip two content bytes
-
- // 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.
- check_length(v.size(), 2, current_idx + 1);
- const int half = (v[current_idx + 1] << 8) + v[current_idx + 2];
- 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<double>::infinity()
- : std::numeric_limits<double>::quiet_NaN();
- }
- return (half & 0x8000) != 0 ? -val : val;
- }
-
- case 0xfa: // Single-Precision Float (four-byte IEEE 754)
- {
- // copy bytes in reverse order into the float variable
- float res;
- check_length(v.size(), sizeof(float), current_idx + 1);
- for (size_t byte = 0; byte < sizeof(float); ++byte)
- {
- reinterpret_cast<uint8_t *>(&res)[sizeof(float) - byte - 1] =
- v[current_idx + 1 + byte];
- }
- idx += sizeof(float); // skip content bytes
- return res;
- }
-
- case 0xfb: // Double-Precision Float (eight-byte IEEE 754)
- {
- // copy bytes in reverse order into the double variable
- double res;
- check_length(v.size(), sizeof(double), current_idx + 1);
- for (size_t byte = 0; byte < sizeof(double); ++byte)
- {
- reinterpret_cast<uint8_t *>(&res)[sizeof(double) - byte - 1] =
- v[current_idx + 1 + byte];
- }
- idx += sizeof(double); // skip content bytes
- return res;
- }
-
- default: // anything else (0xFF is handled inside the other types)
- {
- std::stringstream ss;
- ss << std::hex << static_cast<int>(v[current_idx]);
- JSON_THROW(parse_error::create(112, current_idx + 1,
- "error reading CBOR; last byte: 0x" +
- ss.str()));
- }
- }
- }
-
-public:
- /*!
- @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 |Â 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 |Â 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 |Â 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.
-
- @param[in] j JSON value to serialize
- @return MessagePack serialization as byte vector
-
- @complexity Linear in the size of the JSON value @a j.
-
- @liveexample{The example shows the serialization of a JSON value to a byte
- vector in MessagePack format.,to_msgpack}
-
- @sa http://msgpack.org
- @sa @ref from_msgpack(const std::vector<uint8_t>&, const size_t) for the
- analogous deserialization
- @sa @ref to_cbor(const basic_json& for the related CBOR format
-
- @since version 2.0.9
- */
- static std::vector<uint8_t> to_msgpack(const basic_json &j)
- {
- std::vector<uint8_t> result;
- to_msgpack_internal(j, result);
- return result;
- }
-
- /*!
- @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.
-
- @liveexample{The example shows the deserialization of a byte vector in
- MessagePack format to a JSON value.,from_msgpack}
-
- @sa http://msgpack.org
- @sa @ref to_msgpack(const basic_json&) for the analogous serialization
- @sa @ref from_cbor(const std::vector<uint8_t>&, const size_t) for the
- related CBOR format
-
- @since version 2.0.9, parameter @a start_index since 2.1.1
- */
- static basic_json from_msgpack(const std::vector<uint8_t> &v,
- const size_t start_index = 0)
- {
- size_t i = start_index;
- return from_msgpack_internal(v, i);
- }
-
- /*!
- @brief create a MessagePack 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)
-
- @param[in] j JSON value to serialize
- @return MessagePack serialization as byte vector
-
- @complexity Linear in the size of the JSON value @a j.
-
- @liveexample{The example shows the serialization of a JSON value to a byte
- vector in CBOR format.,to_cbor}
-
- @sa http://cbor.io
- @sa @ref from_cbor(const std::vector<uint8_t>&, const size_t) for the
- analogous deserialization
- @sa @ref to_msgpack(const basic_json& for the related MessagePack format
-
- @since version 2.0.9
- */
- static std::vector<uint8_t> to_cbor(const basic_json &j)
- {
- std::vector<uint8_t> result;
- to_cbor_internal(j, result);
- return result;
- }
-
- /*!
- @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 |Â `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<uint8_t>&, 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<uint8_t> &v,
- const size_t start_index = 0)
- {
- size_t i = start_index;
- return from_cbor_internal(v, i);
- }
-
- /// @}
-
- ///////////////////////////
- // convenience functions //
- ///////////////////////////
-
- /*!
- @brief return the type as string
-
- 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.
-
- @return basically a string representation of a the @a m_type member
-
- @complexity Constant.
-
- @liveexample{The following code exemplifies `type_name()` for all JSON
- types.,type_name}
-
- @since version 1.0.0, public since 2.1.0
- */
- std::string type_name() const
- {
- {
- 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";
- }
- }
- }
-
-private:
- //////////////////////
- // member variables //
- //////////////////////
-
- /// the type of the current element
- value_t m_type = value_t::null;
-
- /// the value of the current element
- json_value m_value = {};
-
-private:
- ///////////////
- // iterators //
- ///////////////
-
- /*!
- @brief an iterator for primitive JSON types
-
- 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:
- difference_type get_value() const noexcept { return m_it; }
- /// set iterator to a defined beginning
- void set_begin() noexcept { m_it = begin_value; }
-
- /// set iterator to a defined past the end
- void set_end() noexcept { m_it = end_value; }
-
- /// return whether the iterator can be dereferenced
- constexpr bool is_begin() const noexcept
- {
- return (m_it == begin_value);
- }
-
- /// 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);
- }
-
- 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.m_it <= rhs.m_it;
- }
-
- 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.m_it >= rhs.m_it;
- }
-
- primitive_iterator_t operator+(difference_type i)
- {
- auto result = *this;
- result += i;
- return result;
- }
-
- friend constexpr difference_type
- operator-(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept
- {
- return lhs.m_it - rhs.m_it;
- }
-
- friend std::ostream &operator<<(std::ostream &os,
- primitive_iterator_t it)
- {
- return os << it.m_it;
- }
-
- primitive_iterator_t &operator++()
- {
- ++m_it;
- return *this;
- }
-
- primitive_iterator_t operator++(int)
- {
- auto result = *this;
- m_it++;
- return result;
- }
-
- primitive_iterator_t &operator--()
- {
- --m_it;
- return *this;
- }
-
- primitive_iterator_t operator--(int)
- {
- auto result = *this;
- m_it--;
- return result;
- }
-
- primitive_iterator_t &operator+=(difference_type n)
- {
- m_it += n;
- return *this;
- }
-
- primitive_iterator_t &operator-=(difference_type n)
- {
- m_it -= n;
- return *this;
- }
-
- 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<std::ptrdiff_t>::denorm_min();
- };
-
- /*!
- @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()
- {
- }
- };
-
- /// proxy class for the iterator_wrapper functions
- template <typename IteratorType>
- 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;
-
- public:
- explicit iteration_proxy_internal(IteratorType it) noexcept
- : anchor(it)
- {
- }
-
- /// dereference operator (needed for range-based for)
- iteration_proxy_internal &operator*() { return *this; }
-
- /// increment operator (needed for range-based for)
- iteration_proxy_internal &operator++()
- {
- ++anchor;
- ++array_index;
-
- return *this;
- }
-
- /// inequality operator (needed for range-based for)
- bool operator!=(const iteration_proxy_internal &o) const
- {
- return anchor != o.anchor;
- }
-
- /// return key of the iterator
- typename basic_json::string_t key() const
- {
- assert(anchor.m_object != nullptr);
-
- switch (anchor.m_object->type())
- {
- // use integer array index as key
- case value_t::array:
- {
- return std::to_string(array_index);
- }
-
- // use key from the object
- case value_t::object:
- {
- return anchor.key();
- }
-
- // use an empty key for all primitive types
- default:
- {
- return "";
- }
- }
- }
-
- /// return value of the iterator
- typename IteratorType::reference value() const
- {
- return anchor.value();
- }
- };
-
- /// the container to iterate
- typename IteratorType::reference container;
-
- public:
- /// construct iteration proxy from a container
- explicit iteration_proxy(typename IteratorType::reference cont)
- : container(cont)
- {
- }
-
- /// return iterator begin (needed for range-based for)
- iteration_proxy_internal begin() noexcept
- {
- return iteration_proxy_internal(container.begin());
- }
-
- /// return iterator end (needed for range-based for)
- iteration_proxy_internal end() noexcept
- {
- return iteration_proxy_internal(container.end());
- }
- };
-
-public:
- /*!
- @brief a template for a random access iterator for the @ref basic_json class
-
- This class implements a both iterators (iterator and const_iterator) for the
- @ref basic_json class.
-
- @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.**
-
- @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, simplified in version 2.0.9
- */
- template <typename U>
- class iter_impl : public std::iterator<std::random_access_iterator_tag, U>
- {
- /// allow basic_json to access private members
- friend class basic_json;
-
- // make sure U is basic_json or const basic_json
- static_assert(std::is_same<U, basic_json>::value or
- std::is_same<U, const basic_json>::value,
- "iter_impl only accepts (const) 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 std::conditional<std::is_const<U>::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<std::is_const<U>::value,
- typename basic_json::const_reference,
- typename basic_json::reference>::type;
- /// the category of the iterator
- using iterator_category = std::bidirectional_iterator_tag;
-
- /// default constructor
- iter_impl() = default;
-
- /*!
- @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);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- m_it.object_iterator = typename object_t::iterator();
- break;
- }
-
- case basic_json::value_t::array:
- {
- m_it.array_iterator = typename array_t::iterator();
- break;
- }
-
- default:
- {
- m_it.primitive_iterator = primitive_iterator_t();
- break;
- }
- }
- }
-
- /*
- Use operator `const_iterator` instead of `const_iterator(const iterator&
- other) noexcept` to avoid two class definitions for @ref iterator and
- @ref const_iterator.
-
- 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;
-
- if (m_object)
- {
- ret.m_object = m_object;
- ret.m_it = m_it;
- }
-
- return ret;
- }
-
- /*!
- @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)
- {
- }
-
- /*!
- @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<pointer>::value
- and std::is_nothrow_move_assignable<pointer>::value and
- std::is_nothrow_move_constructible<internal_iterator>::value
- and std::is_nothrow_move_assignable<
- internal_iterator>::value)
- {
- std::swap(m_object, other.m_object);
- std::swap(m_it, other.m_it);
- return *this;
- }
-
- 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);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- m_it.object_iterator = m_object->m_value.object->begin();
- break;
- }
-
- case basic_json::value_t::array:
- {
- m_it.array_iterator = m_object->m_value.array->begin();
- break;
- }
-
- case basic_json::value_t::null:
- {
- // set to end so begin()==end() is true: null is empty
- m_it.primitive_iterator.set_end();
- break;
- }
-
- default:
- {
- m_it.primitive_iterator.set_begin();
- break;
- }
- }
- }
-
- /*!
- @brief set the iterator past the last value
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- void set_end() noexcept
- {
- 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;
- }
-
- case basic_json::value_t::array:
- {
- m_it.array_iterator = m_object->m_value.array->end();
- break;
- }
-
- default:
- {
- m_it.primitive_iterator.set_end();
- break;
- }
- }
- }
-
- 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);
-
- 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;
- }
-
- case basic_json::value_t::array:
- {
- assert(m_it.array_iterator != m_object->m_value.array->end());
- return *m_it.array_iterator;
- }
-
- case basic_json::value_t::null:
- {
- JSON_THROW(invalid_iterator::create(214, "cannot get value"));
- }
-
- default:
- {
- if (m_it.primitive_iterator.is_begin())
- {
- return *m_object;
- }
-
- JSON_THROW(invalid_iterator::create(214, "cannot get value"));
- }
- }
- }
-
- /*!
- @brief dereference the iterator
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- pointer operator->() const
- {
- assert(m_object != nullptr);
-
- 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);
- }
-
- case basic_json::value_t::array:
- {
- assert(m_it.array_iterator != m_object->m_value.array->end());
- return &*m_it.array_iterator;
- }
-
- default:
- {
- if (m_it.primitive_iterator.is_begin())
- {
- return m_object;
- }
-
- JSON_THROW(invalid_iterator::create(214, "cannot get value"));
- }
- }
- }
-
- /*!
- @brief post-increment (it++)
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- iter_impl operator++(int)
- {
- auto result = *this;
- ++(*this);
- return result;
- }
-
- /*!
- @brief pre-increment (++it)
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- iter_impl &operator++()
- {
- assert(m_object != nullptr);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- std::advance(m_it.object_iterator, 1);
- break;
- }
-
- case basic_json::value_t::array:
- {
- std::advance(m_it.array_iterator, 1);
- break;
- }
-
- default:
- {
- ++m_it.primitive_iterator;
- break;
- }
- }
-
- return *this;
- }
-
- /*!
- @brief post-decrement (it--)
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- iter_impl operator--(int)
- {
- auto result = *this;
- --(*this);
- return result;
- }
-
- /*!
- @brief pre-decrement (--it)
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- iter_impl &operator--()
- {
- assert(m_object != nullptr);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- std::advance(m_it.object_iterator, -1);
- break;
- }
-
- case basic_json::value_t::array:
- {
- std::advance(m_it.array_iterator, -1);
- break;
- }
-
- default:
- {
- --m_it.primitive_iterator;
- break;
- }
- }
-
- return *this;
- }
-
- /*!
- @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"));
- }
-
- assert(m_object != nullptr);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- return (m_it.object_iterator == other.m_it.object_iterator);
- }
-
- case basic_json::value_t::array:
- {
- return (m_it.array_iterator == other.m_it.array_iterator);
- }
-
- default:
- {
- return (m_it.primitive_iterator ==
- other.m_it.primitive_iterator);
- }
- }
- }
-
- /*!
- @brief comparison: not equal
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- bool operator!=(const iter_impl &other) const
- {
- return not operator==(other);
- }
-
- /*!
- @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"));
- }
-
- assert(m_object != nullptr);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- JSON_THROW(invalid_iterator::create(
- 213, "cannot compare order of object iterators"));
- }
-
- case basic_json::value_t::array:
- {
- return (m_it.array_iterator < other.m_it.array_iterator);
- }
-
- default:
- {
- return (m_it.primitive_iterator <
- other.m_it.primitive_iterator);
- }
- }
- }
-
- /*!
- @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);
- }
-
- /*!
- @brief comparison: greater than
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- bool operator>(const iter_impl &other) const
- {
- return not operator<=(other);
- }
-
- /*!
- @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);
- }
-
- /*!
- @brief add to iterator
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- iter_impl &operator+=(difference_type i)
- {
- assert(m_object != nullptr);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- JSON_THROW(invalid_iterator::create(
- 209, "cannot use offsets with object iterators"));
- }
-
- case basic_json::value_t::array:
- {
- std::advance(m_it.array_iterator, i);
- break;
- }
-
- default:
- {
- m_it.primitive_iterator += i;
- break;
- }
- }
-
- return *this;
- }
-
- /*!
- @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;
- }
-
- /*!
- @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:
- {
- JSON_THROW(invalid_iterator::create(
- 209, "cannot use offsets with object iterators"));
- }
-
- case basic_json::value_t::array:
- {
- return m_it.array_iterator - other.m_it.array_iterator;
- }
-
- default:
- {
- return m_it.primitive_iterator - other.m_it.primitive_iterator;
- }
- }
- }
-
- /*!
- @brief access to successor
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- reference operator[](difference_type n) const
- {
- assert(m_object != nullptr);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- JSON_THROW(invalid_iterator::create(
- 208, "cannot use operator[] for object iterators"));
- }
-
- case basic_json::value_t::array:
- {
- return *std::next(m_it.array_iterator, n);
- }
-
- case basic_json::value_t::null:
- {
- JSON_THROW(invalid_iterator::create(214, "cannot get value"));
- }
-
- default:
- {
- if (m_it.primitive_iterator.get_value() == -n)
- {
- return *m_object;
- }
-
- JSON_THROW(invalid_iterator::create(214, "cannot get value"));
- }
- }
- }
-
- /*!
- @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;
- }
-
- JSON_THROW(invalid_iterator::create(
- 207, "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 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 <typename Base>
- class json_reverse_iterator : public std::reverse_iterator<Base>
- {
- public:
- /// shortcut to the reverse iterator adaptor
- using base_iterator = std::reverse_iterator<Base>;
- /// the reference type for the pointed-to element
- using reference = typename Base::reference;
-
- /// create reverse iterator from iterator
- json_reverse_iterator(
- const typename base_iterator::iterator_type &it) noexcept
- : base_iterator(it)
- {
- }
-
- /// create reverse iterator from base class
- json_reverse_iterator(const base_iterator &it) noexcept
- : base_iterator(it)
- {
- }
-
- /// post-increment (it++)
- json_reverse_iterator operator++(int)
- {
- return base_iterator::operator++(1);
- }
-
- /// pre-increment (++it)
- json_reverse_iterator &operator++()
- {
- base_iterator::operator++();
- return *this;
- }
-
- /// post-decrement (it--)
- json_reverse_iterator operator--(int)
- {
- return base_iterator::operator--(1);
- }
-
- /// pre-decrement (--it)
- json_reverse_iterator &operator--()
- {
- base_iterator::operator--();
- return *this;
- }
-
- /// add to iterator
- json_reverse_iterator &operator+=(difference_type i)
- {
- base_iterator::operator+=(i);
- return *this;
- }
-
- /// add to iterator
- json_reverse_iterator operator+(difference_type i) const
- {
- auto result = *this;
- result += i;
- return result;
- }
-
- /// subtract from iterator
- json_reverse_iterator operator-(difference_type i) const
- {
- auto result = *this;
- result -= i;
- return result;
- }
-
- /// return difference
- difference_type operator-(const json_reverse_iterator &other) const
- {
- return this->base() - other.base();
- }
-
- /// access to successor
- reference operator[](difference_type n) const
- {
- return *(this->operator+(n));
- }
-
- /// 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:
- //////////////////////
- // lexer and parser //
- //////////////////////
-
- /*!
- @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.
- */
- 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_unsigned, ///< an unsigned integer -- use get_number() for
- /// actual value
- value_integer, ///< a signed integer -- use get_number() for actual
- /// value
- value_float, ///< an floating point 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;
- }
-
- /*!
- @brief a lexer from an input stream
- @throw parse_error.111 if input stream is in a bad state
- */
- explicit lexer(std::istream &s) : m_stream(&s), m_line_buffer()
- {
- // immediately abort if stream is erroneous
- if (s.fail())
- {
- JSON_THROW(parse_error::create(111, 0, "bad input stream"));
- }
-
- // 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 parse_error.102 if the low surrogate is invalid; example:
- `""missing or wrong low surrogate""`
- @throw parse_error.103 if code point is > 0x10ffff; example: `"code
- points above 0x10FFFF are invalid"`
-
- @complexity Constant.
-
- @see <http://en.wikipedia.org/wiki/UTF-8#Sample_code>
- */
- string_t to_unicode(const std::size_t codepoint1,
- const std::size_t codepoint2 = 0) const
- {
- // 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
- {
- JSON_THROW(parse_error::create(
- 102, get_position(), "missing or wrong low surrogate"));
- }
- }
-
- string_t result;
-
- if (codepoint < 0x80)
- {
- // 1-byte characters: 0xxxxxxx (ASCII)
- result.append(
- 1, static_cast<typename string_t::value_type>(codepoint));
- }
- else if (codepoint <= 0x7ff)
- {
- // 2-byte characters: 110xxxxx 10xxxxxx
- result.append(1, static_cast<typename string_t::value_type>(
- 0xC0 | (codepoint >> 6)));
- result.append(1, static_cast<typename string_t::value_type>(
- 0x80 | (codepoint & 0x3F)));
- }
- else if (codepoint <= 0xffff)
- {
- // 3-byte characters: 1110xxxx 10xxxxxx 10xxxxxx
- result.append(1, static_cast<typename string_t::value_type>(
- 0xE0 | (codepoint >> 12)));
- result.append(1, static_cast<typename string_t::value_type>(
- 0x80 | ((codepoint >> 6) & 0x3F)));
- result.append(1, static_cast<typename string_t::value_type>(
- 0x80 | (codepoint & 0x3F)));
- }
- else if (codepoint <= 0x10ffff)
- {
- // 4-byte characters: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
- result.append(1, static_cast<typename string_t::value_type>(
- 0xF0 | (codepoint >> 18)));
- result.append(1, static_cast<typename string_t::value_type>(
- 0x80 | ((codepoint >> 12) & 0x3F)));
- result.append(1, static_cast<typename string_t::value_type>(
- 0x80 | ((codepoint >> 6) & 0x3F)));
- result.append(1, static_cast<typename string_t::value_type>(
- 0x80 | (codepoint & 0x3F)));
- }
- else
- {
- JSON_THROW(parse_error::create(
- 103, get_position(),
- "code points above 0x10FFFF are invalid"));
- }
-
- return result;
- }
-
- /// return name of values of type token_type (only used for errors)
- static std::string token_type_name(const token_type t)
- {
- switch (t)
- {
- case token_type::uninitialized:
- return "<uninitialized>";
- case token_type::literal_true:
- return "true literal";
- case token_type::literal_false:
- return "false literal";
- case token_type::literal_null:
- return "null literal";
- case token_type::value_string:
- return "string literal";
- 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 "'['";
- case token_type::begin_object:
- return "'{'";
- case token_type::end_array:
- return "']'";
- case token_type::end_object:
- return "'}'";
- case token_type::name_separator:
- return "':'";
- case token_type::value_separator:
- return "','";
- case token_type::parse_error:
- return "<parse error>";
- case token_type::end_of_input:
- return "end of input";
- default:
- {
- // catch non-enum values
- return "unknown token"; // LCOV_EXCL_LINE
- }
- }
- }
-
- /*!
- 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.
-
- @return the class of the next token read from the buffer
-
- @complexity Linear in the length of the input.\n
-
- Proposition: The loop below will always terminate for finite input.\n
-
- 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 is the continue statement for
- whitespace. To loop forever, the input must be an infinite sequence
- whitespace. This contradicts the assumption of finite input, q.e.d.
- */
- token_type scan()
- {
- while (true)
- {
- // 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;
- }
- {
- position += static_cast<size_t>((m_cursor - m_start));
- 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_43;
- }
- if (yych <= '9')
- {
- goto basic_json_parser_45;
- }
- goto basic_json_parser_5;
- basic_json_parser_13:
- yyaccept = 1;
- yych = *(m_marker = ++m_cursor);
- if (yych <= '9')
- {
- if (yych == '.')
- {
- goto basic_json_parser_47;
- }
- if (yych >= '0')
- {
- goto basic_json_parser_48;
- }
- }
- else
- {
- if (yych <= 'E')
- {
- if (yych >= 'E')
- {
- goto basic_json_parser_51;
- }
- }
- else
- {
- if (yych == 'e')
- {
- goto basic_json_parser_51;
- }
- }
- }
- basic_json_parser_14:
- {
- last_token_type = token_type::value_unsigned;
- 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_47;
- }
- goto basic_json_parser_14;
- }
- else
- {
- if (yych <= 'E')
- {
- goto basic_json_parser_51;
- }
- if (yych == 'e')
- {
- goto basic_json_parser_51;
- }
- 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_52;
- }
- goto basic_json_parser_5;
- basic_json_parser_24:
- yyaccept = 0;
- yych = *(m_marker = ++m_cursor);
- if (yych == 'u')
- {
- goto basic_json_parser_53;
- }
- goto basic_json_parser_5;
- basic_json_parser_25:
- yyaccept = 0;
- yych = *(m_marker = ++m_cursor);
- if (yych == 'r')
- {
- goto basic_json_parser_54;
- }
- 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 <= 1)
- {
- if (yyaccept == 0)
- {
- goto basic_json_parser_5;
- }
- else
- {
- goto basic_json_parser_14;
- }
- }
- else
- {
- if (yyaccept == 2)
- {
- goto basic_json_parser_44;
- }
- else
- {
- goto basic_json_parser_58;
- }
- }
- basic_json_parser_33:
- ++m_cursor;
- {
- last_token_type = token_type::value_string;
- break;
- }
- basic_json_parser_35:
- ++m_cursor;
- if (m_limit <= m_cursor)
- {
- fill_line_buffer(1); // LCOV_EXCL_LINE
- }
- yych = *m_cursor;
- if (yych <= 'e')
- {
- if (yych <= '/')
- {
- if (yych == '"')
- {
- goto basic_json_parser_30;
- }
- if (yych <= '.')
- {
- goto basic_json_parser_32;
- }
- goto basic_json_parser_30;
- }
- else
- {
- if (yych <= '\\')
- {
- if (yych <= '[')
- {
- goto basic_json_parser_32;
- }
- goto basic_json_parser_30;
- }
- else
- {
- if (yych == 'b')
- {
- goto basic_json_parser_30;
- }
- 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')
- {
- goto basic_json_parser_30;
- }
- goto basic_json_parser_32;
- }
- else
- {
- if (yych <= 't')
- {
- goto basic_json_parser_30;
- }
- if (yych <= 'u')
- {
- goto basic_json_parser_55;
- }
- goto basic_json_parser_32;
- }
- }
- }
- 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:
- yyaccept = 2;
- yych = *(m_marker = ++m_cursor);
- if (yych <= '9')
- {
- if (yych == '.')
- {
- goto basic_json_parser_47;
- }
- if (yych >= '0')
- {
- goto basic_json_parser_48;
- }
- }
- else
- {
- if (yych <= 'E')
- {
- if (yych >= 'E')
- {
- goto basic_json_parser_51;
- }
- }
- else
- {
- if (yych == 'e')
- {
- goto basic_json_parser_51;
- }
- }
- }
- basic_json_parser_44:
- {
- last_token_type = token_type::value_integer;
- break;
- }
- basic_json_parser_45:
- yyaccept = 2;
- m_marker = ++m_cursor;
- if ((m_limit - m_cursor) < 3)
- {
- fill_line_buffer(3); // LCOV_EXCL_LINE
- }
- yych = *m_cursor;
- if (yych <= '9')
- {
- if (yych == '.')
- {
- goto basic_json_parser_47;
- }
- if (yych <= '/')
- {
- goto basic_json_parser_44;
- }
- goto basic_json_parser_45;
- }
- else
- {
- if (yych <= 'E')
- {
- if (yych <= 'D')
- {
- goto basic_json_parser_44;
- }
- goto basic_json_parser_51;
- }
- else
- {
- if (yych == 'e')
- {
- goto basic_json_parser_51;
- }
- goto basic_json_parser_44;
- }
- }
- basic_json_parser_47:
- yych = *++m_cursor;
- if (yych <= '/')
- {
- goto basic_json_parser_32;
- }
- if (yych <= '9')
- {
- 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 <= '/')
- {
- goto basic_json_parser_50;
- }
- if (yych <= '9')
- {
- goto basic_json_parser_48;
- }
- basic_json_parser_50:
- {
- last_token_type = token_type::parse_error;
- break;
- }
- basic_json_parser_51:
- yych = *++m_cursor;
- if (yych <= ',')
- {
- if (yych == '+')
- {
- goto basic_json_parser_59;
- }
- goto basic_json_parser_32;
- }
- else
- {
- if (yych <= '-')
- {
- goto basic_json_parser_59;
- }
- if (yych <= '/')
- {
- goto basic_json_parser_32;
- }
- if (yych <= '9')
- {
- goto basic_json_parser_60;
- }
- goto basic_json_parser_32;
- }
- basic_json_parser_52:
- yych = *++m_cursor;
- if (yych == 'l')
- {
- goto basic_json_parser_62;
- }
- goto basic_json_parser_32;
- basic_json_parser_53:
- yych = *++m_cursor;
- if (yych == 'l')
- {
- goto basic_json_parser_63;
- }
- goto basic_json_parser_32;
- basic_json_parser_54:
- yych = *++m_cursor;
- if (yych == 'u')
- {
- goto basic_json_parser_64;
- }
- goto basic_json_parser_32;
- basic_json_parser_55:
- ++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_65;
- }
- goto basic_json_parser_32;
- }
- else
- {
- if (yych <= 'F')
- {
- goto basic_json_parser_65;
- }
- if (yych <= '`')
- {
- goto basic_json_parser_32;
- }
- if (yych <= 'f')
- {
- goto basic_json_parser_65;
- }
- goto basic_json_parser_32;
- }
- basic_json_parser_56:
- yyaccept = 3;
- 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_58;
- }
- if (yych <= '9')
- {
- goto basic_json_parser_56;
- }
- }
- else
- {
- if (yych <= 'E')
- {
- goto basic_json_parser_51;
- }
- if (yych == 'e')
- {
- goto basic_json_parser_51;
- }
- }
- basic_json_parser_58:
- {
- last_token_type = token_type::value_float;
- break;
- }
- basic_json_parser_59:
- yych = *++m_cursor;
- if (yych <= '/')
- {
- goto basic_json_parser_32;
- }
- if (yych >= ':')
- {
- goto basic_json_parser_32;
- }
- basic_json_parser_60:
- ++m_cursor;
- if (m_limit <= m_cursor)
- {
- fill_line_buffer(1); // LCOV_EXCL_LINE
- }
- yych = *m_cursor;
- if (yych <= '/')
- {
- goto basic_json_parser_58;
- }
- if (yych <= '9')
- {
- goto basic_json_parser_60;
- }
- goto basic_json_parser_58;
- basic_json_parser_62:
- yych = *++m_cursor;
- if (yych == 's')
- {
- goto basic_json_parser_66;
- }
- goto basic_json_parser_32;
- basic_json_parser_63:
- yych = *++m_cursor;
- if (yych == 'l')
- {
- goto basic_json_parser_67;
- }
- goto basic_json_parser_32;
- basic_json_parser_64:
- yych = *++m_cursor;
- if (yych == 'e')
- {
- goto basic_json_parser_69;
- }
- goto basic_json_parser_32;
- basic_json_parser_65:
- ++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_71;
- }
- goto basic_json_parser_32;
- }
- else
- {
- if (yych <= 'F')
- {
- goto basic_json_parser_71;
- }
- if (yych <= '`')
- {
- goto basic_json_parser_32;
- }
- if (yych <= 'f')
- {
- goto basic_json_parser_71;
- }
- goto basic_json_parser_32;
- }
- basic_json_parser_66:
- yych = *++m_cursor;
- if (yych == 'e')
- {
- goto basic_json_parser_72;
- }
- goto basic_json_parser_32;
- basic_json_parser_67:
- ++m_cursor;
- {
- last_token_type = token_type::literal_null;
- break;
- }
- basic_json_parser_69:
- ++m_cursor;
- {
- last_token_type = token_type::literal_true;
- break;
- }
- basic_json_parser_71:
- ++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_74;
- }
- goto basic_json_parser_32;
- }
- else
- {
- if (yych <= 'F')
- {
- goto basic_json_parser_74;
- }
- if (yych <= '`')
- {
- goto basic_json_parser_32;
- }
- if (yych <= 'f')
- {
- goto basic_json_parser_74;
- }
- goto basic_json_parser_32;
- }
- basic_json_parser_72:
- ++m_cursor;
- {
- last_token_type = token_type::literal_false;
- break;
- }
- basic_json_parser_74:
- ++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_30;
- }
- goto basic_json_parser_32;
- }
- else
- {
- if (yych <= 'F')
- {
- goto basic_json_parser_30;
- }
- if (yych <= '`')
- {
- goto basic_json_parser_32;
- }
- if (yych <= 'f')
- {
- goto basic_json_parser_30;
- }
- goto basic_json_parser_32;
- }
- }
- }
-
- position += static_cast<size_t>((m_cursor - m_start));
- return last_token_type;
- }
-
- /*!
- @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
- */
- void fill_line_buffer(size_t n = 0)
- {
- // if line buffer is used, m_content points to its data
- assert(m_line_buffer.empty() or
- m_content == reinterpret_cast<const lexer_char_t *>(
- m_line_buffer.data()));
-
- // 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());
-
- // 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);
-
- // number of processed characters (p)
- const auto num_processed_chars =
- static_cast<size_t>(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;
-
- // no stream is used or end of file is reached
- if (m_stream == nullptr or m_stream->eof())
- {
- // m_start may or may not be pointing into m_line_buffer at
- // this point. We trust the standard library to do the right
- // thing. See http://stackoverflow.com/q/28142011/266378
- m_line_buffer.assign(m_start, m_limit);
-
- // 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)
- {
- m_line_buffer.append(n - 1, '\x01');
- }
- }
- else
- {
- // 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();
-
- // check if stream is still good
- if (m_stream->fail())
- {
- JSON_THROW(parse_error::create(111, 0, "bad input stream"));
- }
-
- std::getline(*m_stream, m_line_buffer_tmp, '\n');
-
- // add line with newline symbol to the line buffer
- m_line_buffer += m_line_buffer_tmp;
- m_line_buffer.push_back('\n');
- }
-
- // set pointers
- m_content =
- reinterpret_cast<const lexer_char_t *>(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();
- }
-
- /// return string representation of last read token
- string_t get_token_string() const
- {
- assert(m_start != nullptr);
- return string_t(
- reinterpret_cast<typename string_t::const_pointer>(m_start),
- static_cast<size_t>(m_cursor - m_start));
- }
-
- /*!
- @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
- indefinitely 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 parse_error.102 if to_unicode fails or surrogate error
- @throw parse_error.103 if to_unicode fails
- */
- string_t get_string() const
- {
- assert(m_cursor - m_start >= 2);
-
- string_t result;
- result.reserve(static_cast<size_t>(m_cursor - m_start - 2));
-
- // iterate the result between the quotes
- for (const lexer_char_t *i = m_start + 1; i < m_cursor - 1; ++i)
- {
- // find next escape character
- auto e = std::find(i, m_cursor - 1, '\\');
- if (e != i)
- {
- // see
- // https://github.com/nlohmann/json/issues/365#issuecomment-262874705
- for (auto k = i; k < e; k++)
- {
- result.push_back(
- static_cast<typename string_t::value_type>(*k));
- }
- i = e - 1; // -1 because of ++i
- }
- else
- {
- // processing escaped character
- // read next character
- ++i;
-
- 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;
- }
-
- // unicode
- case 'u':
- {
- // get code xxxx from uxxxx
- auto codepoint = std::strtoul(
- std::string(
- reinterpret_cast<
- typename string_t::const_pointer>(i + 1),
- 4)
- .c_str(),
- nullptr, 16);
-
- // 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')
- {
- JSON_THROW(parse_error::create(
- 102, get_position(),
- "missing low surrogate"));
- }
-
- // get code yyyy from uxxxx\uyyyy
- auto codepoint2 = std::strtoul(
- std::string(
- reinterpret_cast<
- typename string_t::const_pointer>(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
- JSON_THROW(parse_error::create(
- 102, get_position(), "missing high surrogate"));
- }
- else
- {
- // add unicode character(s)
- result += to_unicode(codepoint);
- // skip the next four characters (xxxx)
- i += 4;
- }
- break;
- }
- }
- }
- }
-
- return result;
- }
-
- /*!
- @brief parse string into a built-in arithmetic type as if the current
- locale is POSIX.
-
- @note in floating-point case strtod may parse past the token's end -
- this is not an error
-
- @note any leading blanks are not handled
- */
- struct strtonum
- {
- public:
- strtonum(const char *start, const char *end)
- : m_start(start), m_end(end)
- {
- }
-
- /*!
- @return true iff parsed successfully as number of type T
-
- @param[in,out] val shall contain parsed value, or undefined value
- if could not parse
- */
- template <typename T, typename = typename std::enable_if<
- std::is_arithmetic<T>::value>::type>
- bool to(T &val) const
- {
- return parse(val, std::is_integral<T>());
- }
-
- private:
- const char *const m_start = nullptr;
- const char *const m_end = nullptr;
-
- // floating-point conversion
-
- // overloaded wrappers for strtod/strtof/strtold
- // that will be called from parse<floating_point_t>
- static void strtof(float &f, const char *str, char **endptr)
- {
- f = std::strtof(str, endptr);
- }
-
- static void strtof(double &f, const char *str, char **endptr)
- {
- f = std::strtod(str, endptr);
- }
-
- static void strtof(long double &f, const char *str, char **endptr)
- {
- f = std::strtold(str, endptr);
- }
-
- template <typename T>
- bool parse(T &value, /*is_integral=*/std::false_type) const
- {
- // replace decimal separator with locale-specific version,
- // when necessary; data will point to either the original
- // string, or buf, or tempstr containing the fixed string.
- std::string tempstr;
- std::array<char, 64> buf;
- const size_t len = static_cast<size_t>(m_end - m_start);
-
- // lexer will reject empty numbers
- assert(len > 0);
-
- // since dealing with strtod family of functions, we're
- // getting the decimal point char from the C locale facilities
- // instead of C++'s numpunct facet of the current std::locale
- const auto loc = localeconv();
- assert(loc != nullptr);
- const char decimal_point_char = (loc->decimal_point == nullptr)
- ? '.'
- : loc->decimal_point[0];
-
- const char *data = m_start;
-
- if (decimal_point_char != '.')
- {
- const size_t ds_pos = static_cast<size_t>(
- std::find(m_start, m_end, '.') - m_start);
-
- if (ds_pos != len)
- {
- // copy the data into the local buffer or tempstr, if
- // buffer is too small; replace decimal separator, and
- // update data to point to the modified bytes
- if ((len + 1) < buf.size())
- {
- std::copy(m_start, m_end, buf.begin());
- buf[len] = 0;
- buf[ds_pos] = decimal_point_char;
- data = buf.data();
- }
- else
- {
- tempstr.assign(m_start, m_end);
- tempstr[ds_pos] = decimal_point_char;
- data = tempstr.c_str();
- }
- }
- }
-
- char *endptr = nullptr;
- value = 0;
- // this calls appropriate overload depending on T
- strtof(value, data, &endptr);
-
- // parsing was successful iff strtof parsed exactly the number
- // of characters determined by the lexer (len)
- const bool ok = (endptr == (data + len));
-
- if (ok and (value == static_cast<T>(0.0)) and (*data == '-'))
- {
- // some implementations forget to negate the zero
- value = -0.0;
- }
-
- return ok;
- }
-
- // integral conversion
-
- signed long long parse_integral(char **endptr,
- /*is_signed*/ std::true_type) const
- {
- return std::strtoll(m_start, endptr, 10);
- }
-
- unsigned long long
- parse_integral(char **endptr, /*is_signed*/ std::false_type) const
- {
- return std::strtoull(m_start, endptr, 10);
- }
-
- template <typename T>
- bool parse(T &value, /*is_integral=*/std::true_type) const
- {
- char *endptr = nullptr;
- errno = 0; // these are thread-local
- const auto x = parse_integral(&endptr, std::is_signed<T>());
-
- // called right overload?
- static_assert(
- std::is_signed<T>() == std::is_signed<decltype(x)>(), "");
-
- value = static_cast<T>(x);
-
- return (x == static_cast<decltype(x)>(
- value)) // x fits into destination T
- and (x < 0) == (value < 0) // preserved sign
- // and ((x != 0) or is_integral()) // strto[u]ll
- // did nto fail
- and (errno == 0) // strto[u]ll did not overflow
- and (m_start < m_end) // token was not empty
- and (endptr == m_end); // parsed entire token exactly
- }
- };
-
- /*!
- @brief return number value for number tokens
-
- 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.
-
- integral numbers that don't fit into the the range of the respective
- type are parsed as number_float_t
-
- floating-point values do not satisfy std::isfinite predicate
- are converted to value_t::null
-
- throws if the entire string [m_start .. m_cursor) cannot be
- interpreted as a number
-
- @param[out] result @ref basic_json object to receive the number.
- @param[in] token the type of the number token
- */
- bool get_number(basic_json &result, const token_type token) const
- {
- assert(m_start != nullptr);
- assert(m_start < m_cursor);
- assert((token == token_type::value_unsigned) or
- (token == token_type::value_integer) or
- (token == token_type::value_float));
-
- strtonum num_converter(reinterpret_cast<const char *>(m_start),
- reinterpret_cast<const char *>(m_cursor));
-
- switch (token)
- {
- case lexer::token_type::value_unsigned:
- {
- number_unsigned_t val;
- if (num_converter.to(val))
- {
- // parsing successful
- result.m_type = value_t::number_unsigned;
- result.m_value = val;
- return true;
- }
- break;
- }
-
- case lexer::token_type::value_integer:
- {
- number_integer_t val;
- if (num_converter.to(val))
- {
- // parsing successful
- result.m_type = value_t::number_integer;
- result.m_value = val;
- return true;
- }
- break;
- }
-
- default:
- {
- break;
- }
- }
-
- // parse float (either explicitly or because a previous conversion
- // failed)
- number_float_t val;
- if (num_converter.to(val))
- {
- // parsing successful
- result.m_type = value_t::number_float;
- result.m_value = val;
-
- // throw in case of infinity or NAN
- if (not std::isfinite(result.m_value.number_float))
- {
- JSON_THROW(out_of_range::create(
- 406, "number overflow parsing '" + get_token_string() +
- "'"));
- }
-
- return true;
- }
-
- // couldn't parse number in any format
- return false;
- }
-
- constexpr size_t get_position() const { return position; }
-
- 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;
- /// current position in the input (read bytes)
- size_t position = 0;
- };
-
- /*!
- @brief syntax analysis
-
- This class implements a recursive decent parser.
- */
- 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<const typename lexer::lexer_char_t *>(buff),
- std::strlen(buff))
- {
- }
-
- /*!
- @brief a parser reading from an input stream
- @throw parse_error.111 if input stream is in a bad state
- */
- parser(std::istream &is, const parser_callback_t cb = nullptr)
- : callback(cb), m_lexer(is)
- {
- }
-
- /// a parser reading from an iterator range with contiguous storage
- template <class IteratorType,
- typename std::enable_if<
- std::is_same<typename std::iterator_traits<
- IteratorType>::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<const typename lexer::lexer_char_t *>(&(*first)),
- static_cast<size_t>(std::distance(first, last)))
- {
- }
-
- /*!
- @brief public parser interface
- @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()
- {
- // read first token
- get_token();
-
- basic_json result = parse_internal(true);
- result.assert_invariant();
-
- 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);
- }
-
- private:
- /*!
- @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);
-
- switch (last_token)
- {
- case lexer::token_type::begin_object:
- {
- if (keep and
- (not callback or
- ((keep = callback(depth++, parse_event_t::object_start,
- result)) != 0)))
- {
- // explicitly set result to object to cope with {}
- result.m_type = value_t::object;
- result.m_value = value_t::object;
- }
-
- // read next token
- get_token();
-
- // 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);
- }
- return result;
- }
-
- // no comma is expected here
- unexpect(lexer::token_type::value_separator);
-
- // otherwise: parse key-value pairs
- do
- {
- // 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();
-
- bool keep_tag = false;
- if (keep)
- {
- if (callback)
- {
- basic_json k(key);
- keep_tag = callback(depth, parse_event_t::key, k);
- }
- else
- {
- keep_tag = true;
- }
- }
-
- // parse separator (:)
- get_token();
- expect(lexer::token_type::name_separator);
-
- // parse and add value
- get_token();
- auto value = parse_internal(keep);
- if (keep and keep_tag and not value.is_discarded())
- {
- result[key] = std::move(value);
- }
- } 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);
- }
-
- return result;
- }
-
- case lexer::token_type::begin_array:
- {
- if (keep and
- (not callback or
- ((keep = callback(depth++, parse_event_t::array_start,
- result)) != 0)))
- {
- // explicitly set result to object to cope with []
- result.m_type = value_t::array;
- result.m_value = value_t::array;
- }
-
- // read next token
- get_token();
-
- // 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);
- }
- return result;
- }
-
- // no comma is expected here
- unexpect(lexer::token_type::value_separator);
-
- // otherwise: parse values
- do
- {
- // 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));
- }
- } 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);
- }
-
- return result;
- }
-
- 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);
- break;
- }
-
- case lexer::token_type::literal_true:
- {
- get_token();
- result.m_type = value_t::boolean;
- result.m_value = true;
- break;
- }
-
- case lexer::token_type::literal_false:
- {
- get_token();
- result.m_type = value_t::boolean;
- result.m_value = false;
- break;
- }
-
- case lexer::token_type::value_unsigned:
- case lexer::token_type::value_integer:
- case lexer::token_type::value_float:
- {
- m_lexer.get_number(result, last_token);
- get_token();
- break;
- }
-
- default:
- {
- // the last token was unexpected
- unexpect(last_token);
- }
- }
-
- if (keep and callback and
- not callback(depth, parse_event_t::value, result))
- {
- result = basic_json(value_t::discarded);
- }
- return result;
- }
-
- /// get next token from lexer
- typename lexer::token_type get_token()
- {
- last_token = m_lexer.scan();
- 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)
- {
- 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);
- 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)
- {
- 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));
- JSON_THROW(parse_error::create(101, m_lexer.get_position(),
- error_msg));
- }
- }
-
- private:
- /// current level of recursion
- int depth = 0;
- /// callback function
- const parser_callback_t callback = nullptr;
- /// the type of the last read token
- typename lexer::token_type last_token =
- lexer::token_type::uninitialized;
- /// the lexer
- lexer m_lexer;
- };
-
-public:
- /*!
- @brief JSON Pointer
-
- A JSON pointer defines a string syntax for identifying a specific value
- within a JSON document. It can be used with functions `at` and
- `operator[]`. Furthermore, JSON pointers are the base for JSON patches.
-
- @sa [RFC 6901](https://tools.ietf.org/html/rfc6901)
-
- @since version 2.0.0
- */
- class json_pointer
- {
- /// allow basic_json to access private members
- friend class basic_json;
-
- public:
- /*!
- @brief create JSON pointer
-
- Create a JSON pointer according to the syntax described in
- [Section 3 of RFC6901](https://tools.ietf.org/html/rfc6901#section-3).
-
- @param[in] s string representing the JSON pointer; if omitted, the
- empty string is assumed which references the whole JSON
- value
-
- @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}
-
- @since version 2.0.0
- */
- explicit json_pointer(const std::string &s = "")
- : reference_tokens(split(s))
- {
- }
-
- /*!
- @brief return a string representation of the JSON pointer
-
- @invariant For each JSON pointer `ptr`, it holds:
- @code {.cpp}
- ptr == json_pointer(ptr.to_string());
- @endcode
-
- @return a string representation of the JSON pointer
-
- @liveexample{The example shows the result of `to_string`.,
- json_pointer__to_string}
-
- @since version 2.0.0
- */
- std::string to_string() const noexcept
- {
- return std::accumulate(
- reference_tokens.begin(), reference_tokens.end(), std::string{},
- [](const std::string &a, const std::string &b) {
- return a + "/" + escape(b);
- });
- }
-
- /// @copydoc to_string()
- operator std::string() const { return to_string(); }
-
- private:
- /*!
- @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())
- {
- JSON_THROW(
- out_of_range::create(405, "JSON pointer has no parent"));
- }
-
- auto last = reference_tokens.back();
- reference_tokens.pop_back();
- return last;
- }
-
- /// return whether pointer points to the root document
- bool is_root() const { return reference_tokens.empty(); }
-
- json_pointer top() const
- {
- if (is_root())
- {
- JSON_THROW(
- out_of_range::create(405, "JSON pointer has no parent"));
- }
-
- json_pointer result = *this;
- result.reference_tokens = {reference_tokens[0]};
- return result;
- }
-
- /*!
- @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
- {
- pointer result = &j;
-
- // in case no reference tokens exist, return a reference to the
- // JSON value j which will be overwritten by a primitive value
- for (const auto &reference_token : reference_tokens)
- {
- switch (result->m_type)
- {
- case value_t::null:
- {
- if (reference_token == "0")
- {
- // start a new array if reference token is 0
- result = &result->operator[](0);
- }
- else
- {
- // start a new object otherwise
- result = &result->operator[](reference_token);
- }
- break;
- }
-
- case value_t::object:
- {
- // create an entry in the object
- result = &result->operator[](reference_token);
- break;
- }
-
- case value_t::array:
- {
- // create an entry in the array
- JSON_TRY
- {
- result = &result->operator[](
- static_cast<size_type>(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;
- }
-
- /*
- The following code is only reached if there exists a
- reference token _and_ the current value is primitive. In
- this case, we have an error situation, because primitive
- values may only occur as single value; that is, with an
- empty list of reference tokens.
- */
- default:
- {
- JSON_THROW(
- type_error::create(313, "invalid value to unflatten"));
- }
- }
- }
-
- return *result;
- }
-
- /*!
- @brief return a reference to the pointed to value
-
- @note This version does not throw if a value is not present, but tries
- to create nested values instead. For instance, calling this function
- with pointer `"/this/that"` on a null value is equivalent to calling
- `operator[]("this").operator[]("that")` on that value, effectively
- changing the null value to an object.
-
- @param[in] ptr a JSON value
-
- @return reference to the JSON value pointed to by the JSON pointer
-
- @complexity Linear in the length of 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.404 if the JSON pointer can not be resolved
- */
- reference get_unchecked(pointer ptr) const
- {
- for (const auto &reference_token : reference_tokens)
- {
- // convert null values to arrays or objects before continuing
- if (ptr->m_type == value_t::null)
- {
- // check if reference token is a number
- const bool nums = std::all_of(
- reference_token.begin(), reference_token.end(),
- [](const char x) { return (x >= '0' and x <= '9'); });
-
- // change value to array for numbers or "-" or to object
- // otherwise
- if (nums or reference_token == "-")
- {
- *ptr = value_t::array;
- }
- else
- {
- *ptr = value_t::object;
- }
- }
-
- switch (ptr->m_type)
- {
- case value_t::object:
- {
- // use unchecked object access
- ptr = &ptr->operator[](reference_token);
- break;
- }
-
- case value_t::array:
- {
- // error condition (cf. RFC 6901, Sect. 4)
- if (reference_token.size() > 1 and
- reference_token[0] == '0')
- {
- JSON_THROW(parse_error::create(
- 106, 0, "array index '" + reference_token +
- "' must not begin with '0'"));
- }
-
- if (reference_token == "-")
- {
- // explicitly treat "-" as index beyond the end
- ptr = &ptr->operator[](ptr->m_value.array->size());
- }
- else
- {
- // convert array index to number; unchecked access
- JSON_TRY
- {
- ptr = &ptr->operator[](static_cast<size_type>(
- 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:
- {
- JSON_THROW(out_of_range::create(
- 404, "unresolved reference token '" + reference_token +
- "'"));
- }
- }
- }
-
- 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)
- {
- switch (ptr->m_type)
- {
- case value_t::object:
- {
- // note: at performs range check
- ptr = &ptr->at(reference_token);
- break;
- }
-
- case value_t::array:
- {
- if (reference_token == "-")
- {
- // "-" always fails the range check
- 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')
- {
- JSON_THROW(parse_error::create(
- 106, 0, "array index '" + reference_token +
- "' must not begin with '0'"));
- }
-
- // note: at performs range check
- JSON_TRY
- {
- ptr = &ptr->at(
- static_cast<size_type>(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:
- {
- JSON_THROW(out_of_range::create(
- 404, "unresolved reference token '" + reference_token +
- "'"));
- }
- }
- }
-
- return *ptr;
- }
-
- /*!
- @brief return a const reference to the pointed to value
-
- @param[in] ptr a JSON value
-
- @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
- {
- for (const auto &reference_token : reference_tokens)
- {
- switch (ptr->m_type)
- {
- case value_t::object:
- {
- // use unchecked object access
- ptr = &ptr->operator[](reference_token);
- break;
- }
-
- case value_t::array:
- {
- if (reference_token == "-")
- {
- // "-" cannot be used for const access
- 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')
- {
- JSON_THROW(parse_error::create(
- 106, 0, "array index '" + reference_token +
- "' must not begin with '0'"));
- }
-
- // use unchecked array access
- JSON_TRY
- {
- ptr = &ptr->operator[](
- static_cast<size_type>(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:
- {
- JSON_THROW(out_of_range::create(
- 404, "unresolved reference token '" + reference_token +
- "'"));
- }
- }
- }
-
- 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)
- {
- switch (ptr->m_type)
- {
- case value_t::object:
- {
- // note: at performs range check
- ptr = &ptr->at(reference_token);
- break;
- }
-
- case value_t::array:
- {
- if (reference_token == "-")
- {
- // "-" always fails the range check
- 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')
- {
- JSON_THROW(parse_error::create(
- 106, 0, "array index '" + reference_token +
- "' must not begin with '0'"));
- }
-
- // note: at performs range check
- JSON_TRY
- {
- ptr = &ptr->at(
- static_cast<size_type>(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:
- {
- JSON_THROW(out_of_range::create(
- 404, "unresolved reference token '" + reference_token +
- "'"));
- }
- }
- }
-
- return *ptr;
- }
-
- /*!
- @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<std::string>
- split(const std::string &reference_string)
- {
- std::vector<std::string> result;
-
- // special case: empty reference string -> no reference tokens
- if (reference_string.empty())
- {
- return result;
- }
-
- // check if nonempty reference string begins with slash
- if (reference_string[0] != '/')
- {
- JSON_THROW(parse_error::create(
- 107, 1,
- "JSON pointer must be empty or begin with '/' - was: '" +
- reference_string + "'"));
- }
-
- // extract the reference tokens:
- // - slash: position of the last read slash (or end of string)
- // - 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),
- // set the beginning of the first reference token
- start = 1;
- // we can stop if start == string::npos+1 = 0
- start != 0;
- // set the beginning of the next reference token
- // (will eventually be 0 if slash == std::string::npos)
- start = slash + 1,
- // find next slash
- 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('~');
- pos != std::string::npos;
- pos = reference_token.find_first_of('~', pos + 1))
- {
- assert(reference_token[pos] == '~');
-
- // ~ must be followed by 0 or 1
- if (pos == reference_token.size() - 1 or
- (reference_token[pos + 1] != '0' and
- reference_token[pos + 1] != '1'))
- {
- JSON_THROW(parse_error::create(
- 108, 0, "escape character '~' must be followed "
- "with '0' or '1'"));
- }
- }
-
- // finally, store the reference token
- unescape(reference_token);
- result.push_back(reference_token);
- }
-
- return result;
- }
-
- /*!
- @brief replace all occurrences of a substring by another string
-
- @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
-
- @pre The search string @a f must not be empty. **This precondition is
- enforced with an assertion.**
-
- @since version 2.0.0
- */
- static void replace_substring(std::string &s, const std::string &f,
- const std::string &t)
- {
- assert(not f.empty());
-
- for (size_t pos = s.find(f); // find first occurrence of f
- pos != std::string::npos; // make sure f was found
- s.replace(pos, f.size(), t), // replace with t
- pos = s.find(f, pos + t.size()) // find next occurrence of f
- )
- ;
- }
-
- /// escape tilde and slash
- static std::string escape(std::string s)
- {
- // escape "~"" to "~0" and "/" to "~1"
- replace_substring(s, "~", "~0");
- replace_substring(s, "/", "~1");
- return s;
- }
-
- /// unescape tilde and slash
- static void unescape(std::string &s)
- {
- // first transform any occurrence of the sequence '~1' to '/'
- replace_substring(s, "~1", "/");
- // then transform any occurrence of the sequence '~0' to '~'
- replace_substring(s, "~0", "~");
- }
-
- /*!
- @param[in] reference_string the reference string to the current value
- @param[in] value the value to consider
- @param[in,out] result the result object to insert values to
-
- @note Empty objects or arrays are flattened to `null`.
- */
- static void flatten(const std::string &reference_string,
- const basic_json &value, basic_json &result)
- {
- switch (value.m_type)
- {
- case value_t::array:
- {
- if (value.m_value.array->empty())
- {
- // flatten empty array as null
- result[reference_string] = nullptr;
- }
- else
- {
- // iterate array and use index as reference string
- for (size_t i = 0; i < value.m_value.array->size(); ++i)
- {
- flatten(reference_string + "/" + std::to_string(i),
- value.m_value.array->operator[](i), result);
- }
- }
- break;
- }
-
- case value_t::object:
- {
- if (value.m_value.object->empty())
- {
- // flatten empty object as null
- result[reference_string] = nullptr;
- }
- else
- {
- // iterate object and use keys as reference string
- for (const auto &element : *value.m_value.object)
- {
- flatten(reference_string + "/" + escape(element.first),
- element.second, result);
- }
- }
- break;
- }
-
- default:
- {
- // add primitive value with its reference string
- result[reference_string] = value;
- break;
- }
- }
- }
-
- /*!
- @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())
- {
- JSON_THROW(
- type_error::create(314, "only objects can be unflattened"));
- }
-
- basic_json result;
-
- // iterate the JSON object values
- for (const auto &element : *value.m_value.object)
- {
- if (not element.second.is_primitive())
- {
- JSON_THROW(type_error::create(
- 315, "values in object must be primitive"));
- }
-
- // assign value to reference pointed to by JSON pointer; Note
- // that if the JSON pointer is "" (i.e., points to the whole
- // value), function get_and_create returns a reference to
- // result itself. An assignment will then create a primitive
- // value.
- json_pointer(element.first).get_and_create(result) =
- element.second;
- }
-
- return result;
- }
-
- 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<std::string> reference_tokens{};
- };
-
- //////////////////////////
- // JSON Pointer support //
- //////////////////////////
-
- /// @name JSON Pointer functions
- /// @{
-
- /*!
- @brief access specified element via JSON Pointer
-
- Uses a JSON pointer to retrieve a reference to the respective JSON value.
- No bound checking is performed. Similar to @ref operator[](const typename
- object_t::key_type&), `null` values are created in arrays and objects if
- necessary.
-
- In particular:
- - If the JSON pointer points to an object key that does not exist, it
- is created an filled with a `null` value before a reference to it
- is returned.
- - If the JSON pointer points to an array index that does not exist, it
- is created an filled with a `null` value before a reference to it
- is returned. All indices between the current maximum and the given
- index are also filled with `null`.
- - The special value `-` is treated as a synonym for the index past the
- end.
-
- @param[in] ptr a JSON pointer
-
- @return reference to the element pointed to by @a ptr
-
- @complexity Constant.
-
- @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}
-
- @since version 2.0.0
- */
- reference operator[](const json_pointer &ptr)
- {
- return ptr.get_unchecked(this);
- }
-
- /*!
- @brief access specified element via JSON Pointer
-
- Uses a JSON pointer to retrieve a reference to the respective JSON value.
- No bound checking is performed. The function does not change the JSON
- value; no `null` values are created. In particular, the the special value
- `-` yields an exception.
-
- @param[in] ptr JSON pointer to the desired element
-
- @return const reference to the element pointed to by @a ptr
-
- @complexity Constant.
-
- @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}
-
- @since version 2.0.0
- */
- const_reference operator[](const json_pointer &ptr) const
- {
- return ptr.get_unchecked(this);
- }
-
- /*!
- @brief access specified element via JSON Pointer
-
- Returns a reference to the element at with specified JSON pointer @a ptr,
- with bounds checking.
-
- @param[in] ptr JSON pointer to the desired element
-
- @return reference to the element pointed to by @a ptr
-
- @throw parse_error.106 if an array index in the passed JSON pointer @a ptr
- begins with '0'. See example below.
-
- @throw parse_error.109 if an array index in the passed JSON pointer @a ptr
- is not a number. See example below.
-
- @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) { return ptr.get_checked(this); }
-
- /*!
- @brief access specified element via JSON Pointer
-
- Returns a const reference to the element at with specified JSON pointer @a
- ptr, with bounds checking.
-
- @param[in] ptr JSON pointer to the desired element
-
- @return reference to the element pointed to by @a ptr
-
- @throw parse_error.106 if an array index in the passed JSON pointer @a ptr
- begins with '0'. See example below.
-
- @throw parse_error.109 if an array index in the passed JSON pointer @a ptr
- is not a number. See example below.
-
- @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
- {
- return ptr.get_checked(this);
- }
-
- /*!
- @brief return flattened JSON value
-
- The function creates a JSON object whose keys are JSON pointers (see [RFC
- 6901](https://tools.ietf.org/html/rfc6901)) and whose values are all
- primitive. The original JSON value can be restored using the @ref
- unflatten() function.
-
- @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.
-
- @complexity Linear in the size the JSON value.
-
- @liveexample{The following code shows how a JSON object is flattened to an
- object whose keys consist of JSON pointers.,flatten}
-
- @sa @ref unflatten() for the reverse function
-
- @since version 2.0.0
- */
- basic_json flatten() const
- {
- basic_json result(value_t::object);
- json_pointer::flatten("", *this, result);
- return result;
- }
-
- /*!
- @brief unflatten a previously flattened JSON value
-
- The function restores the arbitrary nesting of a JSON value that has been
- flattened before using the @ref flatten() function. The JSON value must
- meet certain constraints:
- 1. The value must be an object.
- 2. The keys must be JSON pointers (see
- [RFC 6901](https://tools.ietf.org/html/rfc6901))
- 3. The mapped values must be primitive JSON types.
-
- @return the original JSON from a flattened version
-
- @note Empty objects and arrays are flattened by @ref flatten() to `null`
- values and can not unflattened to their original type. Apart from
- this example, for a JSON value `j`, the following is always true:
- `j == j.flatten().unflatten()`.
-
- @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}
-
- @sa @ref flatten() for the reverse function
-
- @since version 2.0.0
- */
- basic_json unflatten() const { return json_pointer::unflatten(*this); }
-
- /// @}
-
- //////////////////////////
- // JSON Patch functions //
- //////////////////////////
-
- /// @name JSON Patch functions
- /// @{
-
- /*!
- @brief applies a JSON patch
-
- [JSON Patch](http://jsonpatch.com) defines a JSON document structure for
- expressing a sequence of operations to apply to a JSON) document. With
- 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
- @return patched document
-
- @note The application of a patch is atomic: Either all operations succeed
- and the patched document is returned or an exception is thrown. In
- any case, the original value is not changed: the patch is applied
- to a copy of the value.
-
- @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.
-
- @liveexample{The following code shows how a JSON patch is applied to a
- value.,patch}
-
- @sa @ref diff -- create a JSON patch by comparing two JSON values
-
- @sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
- @sa [RFC 6901 (JSON Pointer)](https://tools.ietf.org/html/rfc6901)
-
- @since version 2.0.0
- */
- basic_json patch(const basic_json &json_patch) const
- {
- // make a working copy to apply the patch to
- basic_json result = *this;
-
- // the valid JSON Patch operations
- enum class patch_operations
- {
- add,
- remove,
- replace,
- move,
- copy,
- test,
- invalid
- };
-
- const auto get_op = [](const std::string &op) {
- if (op == "add")
- {
- return patch_operations::add;
- }
- if (op == "remove")
- {
- return patch_operations::remove;
- }
- if (op == "replace")
- {
- return patch_operations::replace;
- }
- if (op == "move")
- {
- return patch_operations::move;
- }
- if (op == "copy")
- {
- return patch_operations::copy;
- }
- if (op == "test")
- {
- return patch_operations::test;
- }
-
- return patch_operations::invalid;
- };
-
- // wrapper for "add" operation; add value at ptr
- const auto operation_add = [&result](json_pointer &ptr,
- basic_json val) {
- // adding to the root of the target document means replacing it
- if (ptr.is_root())
- {
- result = val;
- }
- else
- {
- // make sure the top element of the pointer exists
- json_pointer top_pointer = ptr.top();
- if (top_pointer != ptr)
- {
- result.at(top_pointer);
- }
-
- // get reference to parent of JSON pointer ptr
- const auto last_path = ptr.pop_back();
- basic_json &parent = result[ptr];
-
- switch (parent.m_type)
- {
- case value_t::null:
- case value_t::object:
- {
- // use operator[] to add value
- parent[last_path] = val;
- break;
- }
-
- case value_t::array:
- {
- if (last_path == "-")
- {
- // special case: append to back
- parent.push_back(val);
- }
- else
- {
- const auto idx = std::stoi(last_path);
- if (static_cast<size_type>(idx) > parent.size())
- {
- // avoid undefined behavior
- JSON_THROW(out_of_range::create(
- 401, "array index " + std::to_string(idx) +
- " is out of range"));
- }
- else
- {
- // default case: insert add offset
- parent.insert(parent.begin() +
- static_cast<difference_type>(idx),
- val);
- }
- }
- break;
- }
-
- default:
- {
- // if there exists a parent it cannot be primitive
- assert(false); // LCOV_EXCL_LINE
- }
- }
- }
- };
-
- // wrapper for "remove" operation; remove value at ptr
- const auto operation_remove = [&result](json_pointer &ptr) {
- // get reference to parent of JSON pointer ptr
- const auto last_path = ptr.pop_back();
- basic_json &parent = result.at(ptr);
-
- // remove child
- if (parent.is_object())
- {
- // perform range check
- auto it = parent.find(last_path);
- if (it != parent.end())
- {
- parent.erase(it);
- }
- else
- {
- JSON_THROW(out_of_range::create(403, "key '" + last_path +
- "' not found"));
- }
- }
- else if (parent.is_array())
- {
- // note erase performs range check
- parent.erase(static_cast<size_type>(std::stoi(last_path)));
- }
- };
-
- // type check: top level value must be an array
- if (not json_patch.is_array())
- {
- JSON_THROW(parse_error::create(
- 104, 0, "JSON patch must be an array of objects"));
- }
-
- // iterate and apply the operations
- for (const auto &val : json_patch)
- {
- // wrapper to get a value for an operation
- const auto get_value = [&val](const std::string &op,
- const std::string &member,
- bool string_type) -> basic_json & {
- // find value
- auto it = val.m_value.object->find(member);
-
- // context-sensitive error message
- const auto error_msg =
- (op == "op") ? "operation" : "operation '" + op + "'";
-
- // check if desired value is present
- if (it == val.m_value.object->end())
- {
- 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())
- {
- JSON_THROW(parse_error::create(
- 105, 0, error_msg + " must have string member '" +
- member + "'"));
- }
-
- // no error: return value
- return it->second;
- };
-
- // type check: every element of the array must be an object
- if (not val.is_object())
- {
- JSON_THROW(parse_error::create(
- 104, 0, "JSON patch must be an array of objects"));
- }
-
- // collect mandatory members
- const std::string op = get_value("op", "op", true);
- const std::string path = get_value(op, "path", true);
- json_pointer ptr(path);
-
- switch (get_op(op))
- {
- case patch_operations::add:
- {
- operation_add(ptr, get_value("add", "value", false));
- break;
- }
-
- case patch_operations::remove:
- {
- operation_remove(ptr);
- break;
- }
-
- case patch_operations::replace:
- {
- // the "path" location must exist - use at()
- result.at(ptr) = get_value("replace", "value", false);
- break;
- }
-
- case patch_operations::move:
- {
- const std::string from_path = get_value("move", "from", true);
- json_pointer from_ptr(from_path);
-
- // the "from" location must exist - use at()
- basic_json v = result.at(from_ptr);
-
- // The move operation is functionally identical to a
- // "remove" operation on the "from" location, followed
- // immediately by an "add" operation at the target
- // location with the value that was just removed.
- operation_remove(from_ptr);
- operation_add(ptr, v);
- break;
- }
-
- case patch_operations::copy:
- {
- const std::string from_path = get_value("copy", "from", true);
- ;
- const json_pointer from_ptr(from_path);
-
- // the "from" location must exist - use at()
- result[ptr] = result.at(from_ptr);
- break;
- }
-
- case patch_operations::test:
- {
- bool success = false;
- 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));
- }
- JSON_CATCH(out_of_range &)
- {
- // ignore out of range errors: success remains false
- }
-
- // throw an exception if test fails
- if (not success)
- {
- JSON_THROW(other_error::create(501, "unsuccessful: " +
- val.dump()));
- }
-
- break;
- }
-
- case patch_operations::invalid:
- {
- // op must be "add", "remove", "replace", "move", "copy", or
- // "test"
- JSON_THROW(parse_error::create(
- 105, 0, "operation value '" + op + "' is invalid"));
- }
- }
- }
-
- return result;
- }
-
- /*!
- @brief creates a diff as a JSON patch
-
- Creates a [JSON Patch](http://jsonpatch.com) so that value @a source can
- be changed into the value @a target by calling @ref patch function.
-
- @invariant For two JSON values @a source and @a target, the following code
- yields always `true`:
- @code {.cpp}
- source.patch(diff(source, target)) == target;
- @endcode
-
- @note Currently, only `remove`, `add`, and `replace` operations are
- generated.
-
- @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
-
- @complexity Linear in the lengths of @a source and @a target.
-
- @liveexample{The following code shows how a JSON patch is created as a
- diff for two JSON values.,diff}
-
- @sa @ref patch -- apply a JSON patch
-
- @sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
-
- @since version 2.0.0
- */
- static basic_json diff(const basic_json &source, const basic_json &target,
- const std::string &path = "")
- {
- // the patch
- basic_json result(value_t::array);
-
- // if the values are the same, return empty patch
- if (source == target)
- {
- return result;
- }
-
- if (source.type() != target.type())
- {
- // different types: replace value
- result.push_back(
- {{"op", "replace"}, {"path", path}, {"value", target}});
- }
- else
- {
- switch (source.type())
- {
- case value_t::array:
- {
- // first pass: traverse common elements
- size_t i = 0;
- while (i < source.size() and i < target.size())
- {
- // recursive call to compare array values at index i
- auto temp_diff = diff(source[i], target[i],
- path + "/" + std::to_string(i));
- result.insert(result.end(), temp_diff.begin(),
- temp_diff.end());
- ++i;
- }
-
- // i now reached the end of at least one array
- // in a second pass, traverse the remaining elements
-
- // remove my remaining elements
- const auto end_index =
- static_cast<difference_type>(result.size());
- while (i < source.size())
- {
- // add operations in reverse order to avoid invalid
- // indices
- result.insert(
- result.begin() + end_index,
- object({{"op", "remove"},
- {"path", path + "/" + std::to_string(i)}}));
- ++i;
- }
-
- // add other remaining elements
- while (i < target.size())
- {
- result.push_back({{"op", "add"},
- {"path", path + "/" + std::to_string(i)},
- {"value", target[i]}});
- ++i;
- }
-
- break;
- }
-
- case value_t::object:
- {
- // first pass: traverse this object's elements
- for (auto it = source.begin(); it != source.end(); ++it)
- {
- // escape the key name to be used in a JSON patch
- const auto key = json_pointer::escape(it.key());
-
- if (target.find(it.key()) != target.end())
- {
- // recursive call to compare object values at key it
- auto temp_diff = diff(it.value(), target[it.key()],
- path + "/" + key);
- result.insert(result.end(), temp_diff.begin(),
- temp_diff.end());
- }
- else
- {
- // found a key that is not in o -> remove it
- result.push_back(object(
- {{"op", "remove"}, {"path", path + "/" + key}}));
- }
- }
-
- // second pass: traverse other object's elements
- for (auto it = target.begin(); it != target.end(); ++it)
- {
- if (source.find(it.key()) == source.end())
- {
- // found a key that is not in this -> add it
- const auto key = json_pointer::escape(it.key());
- result.push_back({{"op", "add"},
- {"path", path + "/" + key},
- {"value", it.value()}});
- }
- }
-
- break;
- }
-
- default:
- {
- // both primitive type: replace value
- result.push_back(
- {{"op", "replace"}, {"path", path}, {"value", target}});
- break;
- }
- }
- }
-
- return result;
- }
-
- /// @}
-};
-
-/////////////
-// presets //
-/////////////
-
-/*!
-@brief default JSON class
-
-This type is the default specialization of the @ref basic_json class which
-uses the standard template types.
-
-@since version 1.0.0
-*/
-using json = basic_json<>;
-} // namespace nlohmann
-
-///////////////////////
-// nonmember support //
-///////////////////////
-
-// specialization of std::swap, and std::hash
-namespace std
-{
-/*!
-@brief exchanges the values of two JSON objects
-
-@since version 1.0.0
-*/
-template <>
-inline void swap(nlohmann::json &j1, nlohmann::json &j2) noexcept(
- is_nothrow_move_constructible<nlohmann::json>::value
- and is_nothrow_move_assignable<nlohmann::json>::value)
-{
- j1.swap(j2);
-}
-
-/// hash value for JSON objects
-template <>
-struct hash<nlohmann::json>
-{
- /*!
- @brief return a hash value for a JSON object
-
- @since version 1.0.0
- */
- std::size_t operator()(const nlohmann::json &j) const
- {
- // a naive hashing via the string representation
- const auto &h = hash<nlohmann::json::string_t>();
- return h(j.dump());
- }
-};
-
-/// specialization for std::less<value_t>
-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
-
-This operator implements a user-defined string literal for JSON objects. It
-can be used by adding `"_json"` to a string literal and returns a JSON object
-if no parse error occurred.
-
-@param[in] s a string representation of a JSON object
-@param[in] n the length of string @a s
-@return a JSON object
-
-@since version 1.0.0
-*/
-inline nlohmann::json operator"" _json(const char *s, std::size_t n)
-{
- return nlohmann::json::parse(s, s + n);
-}
-
-/*!
-@brief user-defined string literal for JSON pointer
-
-This operator implements a user-defined string literal for JSON Pointers. It
-can be used by adding `"_json_pointer"` to a string literal and returns a JSON
-pointer
-object if no parse error occurred.
-
-@param[in] s a string representation of a JSON Pointer
-@param[in] n the length of string @a s
-@return a JSON pointer object
-
-@since version 2.0.0
-*/
-inline nlohmann::json::json_pointer operator"" _json_pointer(const char *s,
- std::size_t n)
-{
- return nlohmann::json::json_pointer(std::string(s, n));
-}
-
-// restore GCC/clang diagnostic settings
-#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_DEPRECATED
-
-#endif