+++ /dev/null
-/*
- __ _____ _____ _____
- __| | __| | | | 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 <cctype> // isdigit
-#include <ciso646> // and, not, or
-#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 <iomanip> // setw
-#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 <stdexcept> // domain_error, invalid_argument, out_of_range
-#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__) < 40900
- #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 not defined(JSON_NOEXCEPTION) || defined(__EXCEPTIONS)
- #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
-{
-///////////////////////////
-// 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;
-
-// taken from http://stackoverflow.com/a/26936864/266378
-template<typename T>
-using is_unscoped_enum =
- std::integral_constant<bool, std::is_convertible<T, int>::value and
- std::is_enum<T>::value>;
-
-/*
-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
- {
- // replace infinity and NAN by null
- if (not std::isfinite(val))
- {
- j = BasicJsonType{};
- }
- else
- {
- 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<>
-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 UnscopedEnumType,
- enable_if_t<is_unscoped_enum<UnscopedEnumType>::value, int> = 0>
-void to_json(BasicJsonType& j, UnscopedEnumType e) noexcept
-{
- external_constructor<value_t::number_integer>::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);
-}
-
-
-///////////////
-// 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(
- std::domain_error("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(std::domain_error("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(std::domain_error("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 UnscopedEnumType,
- enable_if_t<is_unscoped_enum<UnscopedEnumType>::value, int> = 0>
-void from_json(const BasicJsonType& j, UnscopedEnumType& e)
-{
- typename std::underlying_type<UnscopedEnumType>::type val;
- get_arithmetic_value(j, val);
- e = static_cast<UnscopedEnumType>(val);
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::array_t& arr)
-{
- if (not j.is_array())
- {
- JSON_THROW(std::domain_error("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>
-void from_json(const BasicJsonType& j, std::forward_list<T, Allocator>& l)
-{
- // do not perform the check when user wants to retrieve jsons
- // (except when it's null.. ?)
- if (j.is_null())
- {
- JSON_THROW(std::domain_error("type must be array, but is " + j.type_name()));
- }
- if (not std::is_same<T, BasicJsonType>::value)
- {
- if (not j.is_array())
- {
- JSON_THROW(std::domain_error("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
- not std::is_same<typename BasicJsonType::array_t, CompatibleArrayType>::value, int> = 0>
-void from_json(const BasicJsonType& j, CompatibleArrayType& arr)
-{
- if (j.is_null())
- {
- JSON_THROW(std::domain_error("type must be array, but is " + j.type_name()));
- }
-
- // when T == BasicJsonType, do not check if value_t is correct
- if (not std::is_same<typename CompatibleArrayType::value_type, BasicJsonType>::value)
- {
- if (not j.is_array())
- {
- JSON_THROW(std::domain_error("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(std::domain_error("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(std::domain_error("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>;
-
- /////////////////////
- // 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(std::domain_error("961c151d2e87f2686a955a9be24d316f1362bf21 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.
-
- @throw std::bad_alloc if allocation for object, array, or string value
- fails
-
- @liveexample{The following code shows the constructor for different @ref
- value_t values,basic_json__value_t}
-
- @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 std::domain_error if @a type_deduction is `false`, @a manual_type
- is `value_t::object`, but @a init contains an element which is not a pair
- whose first element is a string; example: `"cannot create object from
- initializer list"`
-
- @complexity 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(std::domain_error("cannot create object from initializer list"));
- }
- }
-
- if (is_an_object)
- {
- // the initializer list is a list of pairs -> create object
- m_type = value_t::object;
- m_value = value_t::object;
-
- std::for_each(init.begin(), init.end(), [this](const basic_json & element)
- {
- m_value.object->emplace(*(element[0].m_value.string), element[1]);
- });
- }
- else
- {
- // the initializer list describes an array -> create array
- m_type = value_t::array;
- m_value.array = create<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 std::domain_error if @a init is not a pair whose first elements are
- strings; thrown by
- @ref basic_json(std::initializer_list<basic_json>, bool, value_t)
-
- @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, std::out_of_range is thrown.
- - In case of structured types (array, object), the constructor behaves as
- similar versions for `std::vector`.
- - In case of a null type, std::domain_error is thrown.
-
- @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.**
-
- @throw std::domain_error if iterators are not compatible; that is, do not
- belong to the same JSON value; example: `"iterators are not compatible"`
- @throw std::out_of_range if iterators are for a primitive type (number,
- boolean, or string) where an out of range error can be detected easily;
- example: `"iterators out of range"`
- @throw std::bad_alloc if allocation for object, array, or string fails
- @throw std::domain_error if called with a null value; example: `"cannot
- use construct with iterators from null"`
-
- @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(std::domain_error("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(std::out_of_range("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(std::domain_error("cannot use construct with iterators from " + first.m_object->type_name()));
- }
- }
-
- assert_invariant();
- }
-
- /*!
- @brief construct a JSON value given an input 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)
-
- @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.
-
- @deprecated This constructor is deprecated and will be removed in version
- 3.0.0 to unify the interface of the library. Deserialization will be
- done by stream operators or by calling one of the `parse` functions,
- e.g. @ref parse(std::istream&, const parser_callback_t). That is, calls
- like `json j(i);` for an input stream @a i need to be replaced by
- `json j = json::parse(i);`. See the example below.
-
- @liveexample{The example below demonstrates constructing a JSON value from
- a `std::stringstream` with and without callback
- function.,basic_json__istream}
-
- @since version 2.0.0, deprecated in version 2.0.3, to be removed in
- version 3.0.0
- */
- JSON_DEPRECATED
- explicit basic_json(std::istream& i, const parser_callback_t cb = nullptr)
- {
- *this = parser(i, cb).parse();
- 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)`.
-
- @throw std::bad_alloc if allocation for object, array, or string fails.
-
- @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;
-
- if (indent >= 0)
- {
- dump(ss, true, static_cast<unsigned int>(indent));
- }
- else
- {
- dump(ss, 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(std::domain_error("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 std::domain_error 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(std::domain_error("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
- std::domain_error otherwise
-
- @throw std::domain_error in case passed type @a ReferenceType is
- incompatible with the stored JSON value
-
- @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 std::domain_error in case passed type @a ValueType is incompatible
- to JSON, thrown by @ref get() const
-
- @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
- , 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 std::domain_error if the JSON value is not an array; example:
- `"cannot use at() with string"`
- @throw std::out_of_range if the index @a idx is out of range of the array;
- that is, `idx >= size()`; example: `"array index 7 is out of range"`
-
- @complexity Constant.
-
- @liveexample{The example below shows how array elements can be read and
- written using `at()`.,at__size_type}
-
- @since version 1.0.0
- */
- 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(std::out_of_range("array index " + std::to_string(idx) + " is out of range"));
- }
- }
- else
- {
- JSON_THROW(std::domain_error("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 std::domain_error if the JSON value is not an array; example:
- `"cannot use at() with string"`
- @throw std::out_of_range if the index @a idx is out of range of the array;
- that is, `idx >= size()`; example: `"array index 7 is out of range"`
-
- @complexity Constant.
-
- @liveexample{The example below shows how array elements can be read using
- `at()`.,at__size_type_const}
-
- @since version 1.0.0
- */
- 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(std::out_of_range("array index " + std::to_string(idx) + " is out of range"));
- }
- }
- else
- {
- JSON_THROW(std::domain_error("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 std::domain_error if the JSON value is not an object; example:
- `"cannot use at() with boolean"`
- @throw std::out_of_range if the key @a key is is not stored in the object;
- that is, `find(key) == end()`; example: `"key "the fast" not found"`
-
- @complexity Logarithmic in the size of the container.
-
- @liveexample{The example below shows how object elements can be read and
- written using `at()`.,at__object_t_key_type}
-
- @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
- */
- 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(std::out_of_range("key '" + key + "' not found"));
- }
- }
- else
- {
- JSON_THROW(std::domain_error("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 std::domain_error if the JSON value is not an object; example:
- `"cannot use at() with boolean"`
- @throw std::out_of_range if the key @a key is is not stored in the object;
- that is, `find(key) == end()`; example: `"key "the fast" not found"`
-
- @complexity Logarithmic in the size of the container.
-
- @liveexample{The example below shows how object elements can be read using
- `at()`.,at__object_t_key_type_const}
-
- @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
- */
- 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(std::out_of_range("key '" + key + "' not found"));
- }
- }
- else
- {
- JSON_THROW(std::domain_error("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 std::domain_error if JSON is not an array or null; example:
- `"cannot use operator[] with string"`
-
- @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(std::domain_error("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 std::domain_error if JSON is not an array; example: `"cannot use
- operator[] with null"`
-
- @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(std::domain_error("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 std::domain_error if JSON is not an object or null; example:
- `"cannot use operator[] with string"`
-
- @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(std::domain_error("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 std::domain_error if JSON is not an object; example: `"cannot use
- operator[] with null"`
-
- @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(std::domain_error("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 std::domain_error if JSON is not an object or null; example:
- `"cannot use operator[] with string"`
-
- @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 std::domain_error if JSON is not an object; example: `"cannot use
- operator[] with null"`
-
- @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 std::domain_error if JSON is not an object or null; example:
- `"cannot use operator[] with string"`
-
- @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(std::domain_error("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 std::domain_error if JSON is not an object; example: `"cannot use
- operator[] with null"`
-
- @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(std::domain_error("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(std::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 std::domain_error if JSON is not an object; example: `"cannot use
- value() with null"`
-
- @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(std::domain_error("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(std::out_of_range) {
- return default_value;
- }
- @endcode
-
- @note Unlike @ref at(const json_pointer&), this function does not throw
- if the given key @a key was not found.
-
- @param[in] ptr a JSON pointer to the element to access
- @param[in] default_value the value to return if @a ptr found no value
-
- @tparam ValueType type compatible to JSON values, for instance `int` for
- JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
- JSON arrays. Note the type of the expected value at @a key and the default
- value @a default_value must be compatible.
-
- @return copy of the element at key @a key or @a default_value if @a key
- is not found
-
- @throw std::domain_error if JSON is not an object; example: `"cannot use
- value() with null"`
-
- @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 (std::out_of_range&)
- {
- return default_value;
- }
- }
-
- JSON_THROW(std::domain_error("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 std::out_of_range 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 std::out_of_range when called on `null` value.
-
- @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 std::domain_error if called on a `null` value; example: `"cannot
- use erase() with null"`
- @throw std::domain_error if called on an iterator which does not belong to
- the current JSON value; example: `"iterator does not fit current value"`
- @throw std::out_of_range if called on a primitive type with invalid
- iterator (i.e., any iterator which is not `begin()`); example: `"iterator
- out of range"`
-
- @complexity 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(std::domain_error("iterator does not fit current value"));
- }
-
- IteratorType result = end();
-
- switch (m_type)
- {
- case value_t::boolean:
- case value_t::number_float:
- case value_t::number_integer:
- case value_t::number_unsigned:
- case value_t::string:
- {
- if (not pos.m_it.primitive_iterator.is_begin())
- {
- JSON_THROW(std::out_of_range("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(std::domain_error("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 std::domain_error if called on a `null` value; example: `"cannot
- use erase() with null"`
- @throw std::domain_error if called on iterators which does not belong to
- the current JSON value; example: `"iterators do not fit current value"`
- @throw std::out_of_range if called on a primitive type with invalid
- iterators (i.e., if `first != begin()` and `last != end()`); example:
- `"iterators out of range"`
-
- @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(std::domain_error("iterators do not fit current value"));
- }
-
- IteratorType result = end();
-
- switch (m_type)
- {
- case value_t::boolean:
- case value_t::number_float:
- case value_t::number_integer:
- 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(std::out_of_range("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(std::domain_error("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 std::domain_error 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(std::domain_error("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 std::domain_error when called on a type other than JSON array;
- example: `"cannot use erase() with null"`
- @throw std::out_of_range when `idx >= size()`; example: `"array index 17
- is out of range"`
-
- @complexity Linear in distance between @a idx and the end of the container.
-
- @liveexample{The example shows the effect of `erase()`.,erase__size_type}
-
- @sa @ref erase(IteratorType) -- removes the element at a given position
- @sa @ref erase(IteratorType, IteratorType) -- removes the elements in
- the given range
- @sa @ref erase(const typename object_t::key_type&) -- removes the element
- from an object at the given key
-
- @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(std::out_of_range("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(std::domain_error("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 std::domain_error 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(std::domain_error("cannot use push_back() with " + type_name()));
- }
-
- // transform null object into an array
- if (is_null())
- {
- m_type = value_t::array;
- m_value = value_t::array;
- assert_invariant();
- }
-
- // add element to array (move semantics)
- m_value.array->push_back(std::move(val));
- // invalidate object
- val.m_type = value_t::null;
- }
-
- /*!
- @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(std::domain_error("cannot use push_back() with " + type_name()));
- }
-
- // transform null object into an array
- if (is_null())
- {
- m_type = value_t::array;
- m_value = value_t::array;
- assert_invariant();
- }
-
- // add element to array
- 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 std::domain_error 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(std::domain_error("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 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 std::domain_error 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(std::domain_error("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 std::domain_error 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(std::domain_error("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 std::domain_error if called on JSON values other than arrays;
- example: `"cannot use insert() with string"`
- @throw std::domain_error if @a pos is not an iterator of *this; example:
- `"iterator does not fit current value"`
-
- @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(std::domain_error("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(std::domain_error("cannot use insert() with " + type_name()));
- }
-
- /*!
- @brief inserts element
- @copydoc insert(const_iterator, const basic_json&)
- */
- iterator insert(const_iterator pos, basic_json&& val)
- {
- return insert(pos, val);
- }
-
- /*!
- @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 std::domain_error if called on JSON values other than arrays;
- example: `"cannot use insert() with string"`
- @throw std::domain_error if @a pos is not an iterator of *this; example:
- `"iterator does not fit current value"`
-
- @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(std::domain_error("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(std::domain_error("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 std::domain_error if called on JSON values other than arrays;
- example: `"cannot use insert() with string"`
- @throw std::domain_error if @a pos is not an iterator of *this; example:
- `"iterator does not fit current value"`
- @throw std::domain_error if @a first and @a last do not belong to the same
- JSON value; example: `"iterators do not fit"`
- @throw std::domain_error if @a first or @a last are iterators into
- container for which insert is called; example: `"passed iterators may not
- belong to container"`
-
- @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(std::domain_error("cannot use insert() with " + type_name()));
- }
-
- // check if iterator pos fits to this JSON value
- if (pos.m_object != this)
- {
- JSON_THROW(std::domain_error("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(std::domain_error("iterators do not fit"));
- }
-
- if (first.m_object == this or last.m_object == this)
- {
- JSON_THROW(std::domain_error("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 std::domain_error if called on JSON values other than arrays;
- example: `"cannot use insert() with string"`
- @throw std::domain_error if @a pos is not an iterator of *this; example:
- `"iterator does not fit current value"`
-
- @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(std::domain_error("cannot use insert() with " + type_name()));
- }
-
- // check if iterator pos fits to this JSON value
- if (pos.m_object != this)
- {
- JSON_THROW(std::domain_error("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 std::domain_error 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(std::domain_error("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 std::domain_error 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(std::domain_error("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 std::domain_error 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(std::domain_error("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.
- - Integer and floating-point numbers are automatically converted before
- comparison. Floating-point numbers are compared indirectly: two
- floating-point numbers `f1` and `f2` are considered equal if neither
- `f1 > f2` nor `f2 > f1` holds.
- - Two JSON null values are equal.
-
- @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 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: 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 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);
- }
-
- /// @}
-
-
- ///////////////////
- // serialization //
- ///////////////////
-
- /// @name serialization
- /// @{
-
- /*!
- @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
- j.dump(o, pretty_print, static_cast<unsigned int>(indentation));
-
- return o;
- }
-
- /*!
- @brief serialize to stream
- @copydoc operator<<(std::ostream&, const basic_json&)
- */
- 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
-
- @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
-
- @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
-
- @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
-
- @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
-
- @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
-
- 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 std::invalid_argument in case of parse errors
-
- @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<<(basic_json& j, std::istream& i)
- {
- j = parser(i).parse();
- return i;
- }
-
- /*!
- @brief deserialize from stream
- @copydoc operator<<(basic_json&, std::istream&)
- */
- friend std::istream& operator>>(std::istream& i, basic_json& j)
- {
- j = parser(i).parse();
- return i;
- }
-
- /// @}
-
- //////////////////////////////////////////
- // 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 std::out_of_range 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)
- {
- if (current_index + sizeof(T) + 1 > vec.size())
- {
- JSON_THROW(std::out_of_range("cannot read " + std::to_string(sizeof(T)) + " bytes from vector"));
- }
-
- 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(0x60 + static_cast<uint8_t>(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(0x80 + static_cast<uint8_t>(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(0xa0 + static_cast<uint8_t>(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(std::out_of_range("len out of range"));
- }
-
- // second case: adding offset would result in overflow
- if ((size > (std::numeric_limits<size_t>::max() - offset)))
- {
- JSON_THROW(std::out_of_range("len+offset out of range"));
- }
-
- // last case: reading past the end of the vector
- if (len + offset > size)
- {
- JSON_THROW(std::out_of_range("len+offset out of range"));
- }
- }
-
- /*!
- @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 std::invalid_argument if unsupported features from MessagePack were
- used in the given vector @a v or if the input is not valid MessagePack
- @throw std::out_of_range if the given vector ends prematurely
-
- @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)
- {
- // make sure reading 1 byte is safe
- check_length(v.size(), 1, idx);
-
- // store and increment index
- const size_t current_idx = 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)
- {
- 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;
- for (size_t byte = 0; byte < sizeof(float); ++byte)
- {
- reinterpret_cast<uint8_t*>(&res)[sizeof(float) - byte - 1] = v.at(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;
- for (size_t byte = 0; byte < sizeof(double); ++byte)
- {
- reinterpret_cast<uint8_t*>(&res)[sizeof(double) - byte - 1] = v.at(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)
- {
- 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)
- {
- std::string key = from_msgpack_internal(v, idx);
- result[key] = from_msgpack_internal(v, idx);
- }
- return result;
- }
-
- default:
- {
- JSON_THROW(std::invalid_argument("error parsing a msgpack @ " + std::to_string(current_idx) + ": " + std::to_string(static_cast<int>(v[current_idx]))));
- }
- }
- }
- }
-
- /*!
- @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 std::invalid_argument if unsupported features from CBOR were used in
- the given vector @a v or if the input is not valid CBOR
- @throw std::out_of_range if the given vector ends prematurely
-
- @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++;
-
- switch (v.at(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 (v.at(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 (v.at(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)
- {
- 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)
- {
- 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)
- {
- 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)
- {
- 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)
- {
- 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 (v.at(idx) != 0xff)
- {
- 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.
- const int half = (v.at(current_idx + 1) << 8) + v.at(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;
- for (size_t byte = 0; byte < sizeof(float); ++byte)
- {
- reinterpret_cast<uint8_t*>(&res)[sizeof(float) - byte - 1] = v.at(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;
- for (size_t byte = 0; byte < sizeof(double); ++byte)
- {
- reinterpret_cast<uint8_t*>(&res)[sizeof(double) - byte - 1] = v.at(current_idx + 1 + byte);
- }
- idx += sizeof(double); // skip content bytes
- return res;
- }
-
- default: // anything else (0xFF is handled inside the other types)
- {
- JSON_THROW(std::invalid_argument("error parsing a CBOR @ " + std::to_string(current_idx) + ": " + std::to_string(static_cast<int>(v[current_idx]))));
- }
- }
- }
-
- 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.
-
- @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.
-
- @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 std::invalid_argument if unsupported features from MessagePack were
- used in the given vector @a v or if the input is not valid MessagePack
- @throw std::out_of_range if the given vector ends prematurely
-
- @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.
-
- @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.
-
- @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 std::invalid_argument if unsupported features from CBOR were used in
- the given vector @a v or if the input is not valid MessagePack
- @throw std::out_of_range if the given vector ends prematurely
-
- @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:
- /*!
- @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;
- }
-
- default:
- {
- if (c >= 0x00 and c <= 0x1f)
- {
- // from c (1 byte) to \uxxxx (6 bytes)
- return res + 5;
- }
-
- return res;
- }
- }
- });
- }
-
- /*!
- @brief escape a string
-
- Escape a string by replacing certain special characters by a sequence of
- an escape character (backslash) and another character and other control
- characters by a sequence of "\u" followed by a four-digit hex
- representation.
-
- @param[in] s the string to escape
- @return the escaped string
-
- @complexity Linear in the length of string @a s.
- */
- static string_t escape_string(const string_t& s)
- {
- const auto space = extra_space(s);
- if (space == 0)
- {
- return s;
- }
-
- // 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;
- }
-
- default:
- {
- if (c >= 0x00 and c <= 0x1f)
- {
- // convert a number 0..15 to its hex representation
- // (0..f)
- static const char hexify[16] =
- {
- '0', '1', '2', '3', '4', '5', '6', '7',
- '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
- };
-
- // print character c as \uxxxx
- for (const char m :
- { 'u', '0', '0', hexify[c >> 4], hexify[c & 0x0f]
- })
- {
- result[++pos] = m;
- }
-
- ++pos;
- }
- else
- {
- // all other characters are added as-is
- result[pos++] = c;
- }
- break;
- }
- }
- }
-
- return result;
- }
-
-
- /*!
- @brief locale-independent serialization for built-in arithmetic types
- */
- struct numtostr
- {
- public:
- template<typename NumberType>
- numtostr(NumberType value)
- {
- x_write(value, std::is_integral<NumberType>());
- }
-
- const char* c_str() const
- {
- return m_buf.data();
- }
-
- private:
- /// a (hopefully) large enough character buffer
- std::array < char, 64 > m_buf{{}};
-
- template<typename NumberType>
- void x_write(NumberType x, /*is_integral=*/std::true_type)
- {
- // special case for "0"
- if (x == 0)
- {
- m_buf[0] = '0';
- return;
- }
-
- const bool is_negative = x < 0;
- size_t i = 0;
-
- // spare 1 byte for '\0'
- while (x != 0 and i < m_buf.size() - 1)
- {
- const auto digit = std::labs(static_cast<long>(x % 10));
- m_buf[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 < m_buf.size() - 2);
- m_buf[i++] = '-';
- }
-
- std::reverse(m_buf.begin(), m_buf.begin() + i);
- }
-
- template<typename NumberType>
- void x_write(NumberType x, /*is_integral=*/std::false_type)
- {
- // special case for 0.0 and -0.0
- if (x == 0)
- {
- size_t i = 0;
- if (std::signbit(x))
- {
- m_buf[i++] = '-';
- }
- m_buf[i++] = '0';
- m_buf[i++] = '.';
- m_buf[i] = '0';
- return;
- }
-
- // get number of digits for a text -> float -> text round-trip
- static constexpr auto d = std::numeric_limits<NumberType>::digits10;
-
- // the actual conversion
- const auto written_bytes = snprintf(m_buf.data(), m_buf.size(), "%.*g", d, x);
-
- // negative value indicates an error
- assert(written_bytes > 0);
- // check if buffer was large enough
- assert(static_cast<size_t>(written_bytes) < m_buf.size());
-
- // read information from locale
- const auto loc = localeconv();
- assert(loc != nullptr);
- const char thousands_sep = !loc->thousands_sep ? '\0'
- : loc->thousands_sep[0];
-
- const char decimal_point = !loc->decimal_point ? '\0'
- : loc->decimal_point[0];
-
- // erase thousands separator
- if (thousands_sep != '\0')
- {
- const auto end = std::remove(m_buf.begin(), m_buf.begin() + written_bytes, thousands_sep);
- std::fill(end, m_buf.end(), '\0');
- }
-
- // convert decimal point to '.'
- if (decimal_point != '\0' and decimal_point != '.')
- {
- for (auto& c : m_buf)
- {
- if (c == decimal_point)
- {
- c = '.';
- break;
- }
- }
- }
-
- // determine if need to append ".0"
- size_t i = 0;
- bool value_is_int_like = true;
- for (i = 0; i < m_buf.size(); ++i)
- {
- // break when end of number is reached
- if (m_buf[i] == '\0')
- {
- break;
- }
-
- // check if we find non-int character
- value_is_int_like = value_is_int_like and m_buf[i] != '.' and
- m_buf[i] != 'e' and m_buf[i] != 'E';
- }
-
- if (value_is_int_like)
- {
- // there must be 2 bytes left for ".0"
- assert((i + 2) < m_buf.size());
- // we write to the end of the number
- assert(m_buf[i] == '\0');
- assert(m_buf[i - 1] != '\0');
-
- // add ".0"
- m_buf[i] = '.';
- m_buf[i + 1] = '0';
-
- // the resulting string is properly terminated
- assert(m_buf[i + 2] == '\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. Note that
-
- - strings and object keys are escaped using `escape_string()`
- - integer numbers are converted implicitly via `operator<<`
- - floating-point numbers are converted to a string using `"%g"` format
-
- @param[out] o stream to write to
- @param[in] pretty_print whether the output shall be pretty-printed
- @param[in] indent_step the indent level
- @param[in] current_indent the current indent level (only used internally)
- */
- void dump(std::ostream& o,
- const bool pretty_print,
- const unsigned int indent_step,
- const unsigned int current_indent = 0) const
- {
- // variable to hold indentation for recursive calls
- unsigned int new_indent = current_indent;
-
- switch (m_type)
- {
- case value_t::object:
- {
- if (m_value.object->empty())
- {
- o << "{}";
- return;
- }
-
- o << "{";
-
- // increase indentation
- if (pretty_print)
- {
- new_indent += indent_step;
- o << "\n";
- }
-
- for (auto i = m_value.object->cbegin(); i != m_value.object->cend(); ++i)
- {
- if (i != m_value.object->cbegin())
- {
- o << (pretty_print ? ",\n" : ",");
- }
- o << string_t(new_indent, ' ') << "\""
- << escape_string(i->first) << "\":"
- << (pretty_print ? " " : "");
- i->second.dump(o, pretty_print, indent_step, new_indent);
- }
-
- // decrease indentation
- if (pretty_print)
- {
- new_indent -= indent_step;
- o << "\n";
- }
-
- o << string_t(new_indent, ' ') + "}";
- return;
- }
-
- case value_t::array:
- {
- if (m_value.array->empty())
- {
- o << "[]";
- return;
- }
-
- o << "[";
-
- // increase indentation
- if (pretty_print)
- {
- new_indent += indent_step;
- o << "\n";
- }
-
- for (auto i = m_value.array->cbegin(); i != m_value.array->cend(); ++i)
- {
- if (i != m_value.array->cbegin())
- {
- o << (pretty_print ? ",\n" : ",");
- }
- o << string_t(new_indent, ' ');
- i->dump(o, pretty_print, indent_step, new_indent);
- }
-
- // decrease indentation
- if (pretty_print)
- {
- new_indent -= indent_step;
- o << "\n";
- }
-
- o << string_t(new_indent, ' ') << "]";
- return;
- }
-
- case value_t::string:
- {
- o << string_t("\"") << escape_string(*m_value.string) << "\"";
- return;
- }
-
- case value_t::boolean:
- {
- o << (m_value.boolean ? "true" : "false");
- return;
- }
-
- case value_t::number_integer:
- {
- o << numtostr(m_value.number_integer).c_str();
- return;
- }
-
- case value_t::number_unsigned:
- {
- o << numtostr(m_value.number_unsigned).c_str();
- return;
- }
-
- case value_t::number_float:
- {
- o << numtostr(m_value.number_float).c_str();
- return;
- }
-
- case value_t::discarded:
- {
- o << "<discarded>";
- return;
- }
-
- case value_t::null:
- {
- o << "null";
- return;
- }
- }
- }
-
- 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(std::out_of_range("cannot get value"));
- }
-
- default:
- {
- if (m_it.primitive_iterator.is_begin())
- {
- return *m_object;
- }
-
- JSON_THROW(std::out_of_range("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(std::out_of_range("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(std::domain_error("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(std::domain_error("cannot compare iterators of different containers"));
- }
-
- assert(m_object != nullptr);
-
- switch (m_object->m_type)
- {
- case basic_json::value_t::object:
- {
- JSON_THROW(std::domain_error("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(std::domain_error("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(std::domain_error("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(std::domain_error("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(std::out_of_range("cannot get value"));
- }
-
- default:
- {
- if (m_it.primitive_iterator.get_value() == -n)
- {
- return *m_object;
- }
-
- JSON_THROW(std::out_of_range("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(std::domain_error("cannot use key() for non-object iterators"));
- }
-
- /*!
- @brief return the value of an iterator
- @pre The iterator is initialized; i.e. `m_object != nullptr`.
- */
- reference value() const
- {
- return operator*();
- }
-
- private:
- /// associated JSON instance
- pointer m_object = nullptr;
- /// the actual iterator of the associated instance
- internal_iterator m_it = internal_iterator();
- };
-
- /*!
- @brief a 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;
- }
-
- /// a lexer from an input stream
- explicit lexer(std::istream& s)
- : m_stream(&s), m_line_buffer()
- {
- // immediately abort if stream is erroneous
- if (s.fail())
- {
- JSON_THROW(std::invalid_argument("stream error"));
- }
-
- // fill buffer
- fill_line_buffer();
-
- // skip UTF-8 byte-order mark
- if (m_line_buffer.size() >= 3 and m_line_buffer.substr(0, 3) == "\xEF\xBB\xBF")
- {
- m_line_buffer[0] = ' ';
- m_line_buffer[1] = ' ';
- m_line_buffer[2] = ' ';
- }
- }
-
- // switch off unwanted functions (due to pointer members)
- lexer() = delete;
- lexer(const lexer&) = delete;
- lexer operator=(const lexer&) = delete;
-
- /*!
- @brief create a string from one or two Unicode code points
-
- There are two cases: (1) @a codepoint1 is in the Basic Multilingual
- Plane (U+0000 through U+FFFF) and @a codepoint2 is 0, or (2)
- @a codepoint1 and @a codepoint2 are a UTF-16 surrogate pair to
- represent a code point above U+FFFF.
-
- @param[in] codepoint1 the code point (can be high surrogate)
- @param[in] codepoint2 the code point (can be low surrogate or 0)
-
- @return string representation of the code point; the length of the
- result string is between 1 and 4 characters.
-
- @throw std::out_of_range if code point is > 0x10ffff; example: `"code
- points above 0x10FFFF are invalid"`
- @throw std::invalid_argument if the low surrogate is invalid; example:
- `""missing or wrong low surrogate""`
-
- @complexity Constant.
-
- @see <http://en.wikipedia.org/wiki/UTF-8#Sample_code>
- */
- static string_t to_unicode(const std::size_t codepoint1,
- const std::size_t codepoint2 = 0)
- {
- // calculate the code point from the given code points
- std::size_t codepoint = codepoint1;
-
- // check if codepoint1 is a high surrogate
- if (codepoint1 >= 0xD800 and codepoint1 <= 0xDBFF)
- {
- // check if codepoint2 is a low surrogate
- if (codepoint2 >= 0xDC00 and codepoint2 <= 0xDFFF)
- {
- codepoint =
- // high surrogate occupies the most significant 22 bits
- (codepoint1 << 10)
- // low surrogate occupies the least significant 15 bits
- + codepoint2
- // there is still the 0xD800, 0xDC00 and 0x10000 noise
- // in the result so we have to subtract with:
- // (0xD800 << 10) + DC00 - 0x10000 = 0x35FDC00
- - 0x35FDC00;
- }
- else
- {
- JSON_THROW(std::invalid_argument("missing or wrong low surrogate"));
- }
- }
-
- string_t result;
-
- if (codepoint < 0x80)
- {
- // 1-byte characters: 0xxxxxxx (ASCII)
- result.append(1, static_cast<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) & 0x1F)));
- 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) & 0x0F)));
- 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) & 0x07)));
- 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(std::out_of_range("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 are the continue statements for
- whitespace and byte-order-marks. To loop forever, the input must be an
- infinite sequence of whitespace or byte-order-marks. This contradicts
- the assumption of finite input, q.e.d.
- */
- 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;
- }
- {
- 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;
- }
- }
-
- }
-
- 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();
- 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 std::out_of_range 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(std::invalid_argument("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(std::invalid_argument("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;
-
- // replace infinity and NAN by null
- if (not std::isfinite(result.m_value.number_float))
- {
- result.m_type = value_t::null;
- result.m_value = basic_json::json_value();
- }
-
- return true;
- }
-
- // couldn't parse number in any format
- return false;
- }
-
- 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;
- };
-
- /*!
- @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))
- {}
-
- /// a parser reading from an input stream
- 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)))
- {}
-
- /// public parser interface
- 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:
- /// the actual parser
- 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;
- }
-
- 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(std::invalid_argument(error_msg));
- }
- }
-
- 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(std::invalid_argument(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 std::domain_error if reference token is nonempty and does not
- begin with a slash (`/`); example: `"JSON pointer must be empty or
- begin with /"`
- @throw std::domain_error if a tilde (`~`) is not followed by `0`
- (representing `~`) or `1` (representing `/`); example: `"escape error:
- ~ must be followed with 0 or 1"`
-
- @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:
- /// remove and return last reference pointer
- std::string pop_back()
- {
- if (is_root())
- {
- JSON_THROW(std::domain_error("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(std::domain_error("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.
- */
- 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
- result = &result->operator[](static_cast<size_type>(std::stoi(reference_token)));
- 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(std::domain_error("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 std::out_of_range if the JSON pointer can not be resolved
- @throw std::domain_error if an array index begins with '0'
- @throw std::invalid_argument if an array index was not a number
- */
- 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 std::isdigit(x);
- });
-
- // 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(std::domain_error("array index 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
- ptr = &ptr->operator[](static_cast<size_type>(std::stoi(reference_token)));
- }
- break;
- }
-
- default:
- {
- JSON_THROW(std::out_of_range("unresolved reference token '" + reference_token + "'"));
- }
- }
- }
-
- return *ptr;
- }
-
- 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(std::out_of_range("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(std::domain_error("array index must not begin with '0'"));
- }
-
- // note: at performs range check
- ptr = &ptr->at(static_cast<size_type>(std::stoi(reference_token)));
- break;
- }
-
- default:
- {
- JSON_THROW(std::out_of_range("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
- */
- 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(std::out_of_range("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(std::domain_error("array index must not begin with '0'"));
- }
-
- // use unchecked array access
- ptr = &ptr->operator[](static_cast<size_type>(std::stoi(reference_token)));
- break;
- }
-
- default:
- {
- JSON_THROW(std::out_of_range("unresolved reference token '" + reference_token + "'"));
- }
- }
- }
-
- return *ptr;
- }
-
- 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(std::out_of_range("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(std::domain_error("array index must not begin with '0'"));
- }
-
- // note: at performs range check
- ptr = &ptr->at(static_cast<size_type>(std::stoi(reference_token)));
- break;
- }
-
- default:
- {
- JSON_THROW(std::out_of_range("unresolved reference token '" + reference_token + "'"));
- }
- }
- }
-
- return *ptr;
- }
-
- /// split the string input to reference tokens
- 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(std::domain_error("JSON pointer must be empty or begin with '/'"));
- }
-
- // 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(std::domain_error("escape error: '~' must be followed with '0' or '1'"));
- }
- }
-
- // finally, store the reference token
- unescape(reference_token);
- result.push_back(reference_token);
- }
-
- return result;
- }
-
- private:
- /*!
- @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.
-
- @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
- */
- static basic_json unflatten(const basic_json& value)
- {
- if (not value.is_object())
- {
- JSON_THROW(std::domain_error("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(std::domain_error("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;
- }
-
- private:
- friend bool operator==(json_pointer const& lhs,
- json_pointer const& rhs) noexcept
- {
- return lhs.reference_tokens == rhs.reference_tokens;
- }
-
- friend bool operator!=(json_pointer const& lhs,
- json_pointer const& rhs) noexcept
- {
- return !(lhs == rhs);
- }
-
- /// the reference tokens
- std::vector<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 std::out_of_range if the JSON pointer can not be resolved
- @throw std::domain_error if an array index begins with '0'
- @throw std::invalid_argument if an array index was not a number
-
- @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 std::out_of_range if the JSON pointer can not be resolved
- @throw std::domain_error if an array index begins with '0'
- @throw std::invalid_argument if an array index was not a number
-
- @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
-
- @complexity Constant.
-
- @throw std::out_of_range if the JSON pointer can not be resolved
- @throw std::domain_error if an array index begins with '0'
- @throw std::invalid_argument if an array index was not a number
-
- @liveexample{The behavior is shown in the example.,at_json_pointer}
-
- @since version 2.0.0
- */
- 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
-
- @complexity Constant.
-
- @throw std::out_of_range if the JSON pointer can not be resolved
- @throw std::domain_error if an array index begins with '0'
- @throw std::invalid_argument if an array index was not a number
-
- @liveexample{The behavior is shown in the example.,at_json_pointer_const}
-
- @since version 2.0.0
- */
- 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.
-
- @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 std::out_of_range if a JSON pointer inside the patch could not
- be resolved successfully in the current JSON value; example: `"key baz
- not found"`
- @throw invalid_argument if the JSON patch is malformed (e.g., mandatory
- attributes are missing); example: `"operation add must have member path"`
-
- @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(std::out_of_range("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(std::out_of_range("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
- if (not json_patch.is_array())
- {
- // a JSON patch must be an array of objects
- JSON_THROW(std::invalid_argument("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(std::invalid_argument(error_msg + " must have member '" + member + "'"));
- }
-
- // check if result is of type string
- if (string_type and not it->second.is_string())
- {
- JSON_THROW(std::invalid_argument(error_msg + " must have string member '" + member + "'"));
- }
-
- // no error: return value
- return it->second;
- };
-
- // type check
- if (not val.is_object())
- {
- JSON_THROW(std::invalid_argument("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 (std::out_of_range&)
- {
- // ignore out of range errors: success remains false
- }
-
- // throw an exception if test fails
- if (not success)
- {
- JSON_THROW(std::domain_error("unsuccessful: " + val.dump()));
- }
-
- break;
- }
-
- case patch_operations::invalid:
- {
- // op must be "add", "remove", "replace", "move", "copy", or
- // "test"
- JSON_THROW(std::invalid_argument("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());
- }
-};
-} // 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
-
-// clean up
-#undef JSON_CATCH
-#undef JSON_DEPRECATED
-#undef JSON_THROW
-#undef JSON_TRY
-
-#endif
Code Review / apps / agl-service-windowmanager.git / commitdiff