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11336 lines
375 KiB
Plaintext
11336 lines
375 KiB
Plaintext
/*
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__ _____ _____ _____
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__| | __| | | | JSON for Modern C++
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| | |__ | | | | | | version 2.0.8
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|_____|_____|_____|_|___| https://github.com/nlohmann/json
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Licensed under the MIT License <http://opensource.org/licenses/MIT>.
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Copyright (c) 2013-2016 Niels Lohmann <http://nlohmann.me>.
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Permission is hereby granted, free of charge, to any person obtaining a copy
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of this software and associated documentation files (the "Software"), to deal
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in the Software without restriction, including without limitation the rights
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to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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copies of the Software, and to permit persons to whom the Software is
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furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.
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*/
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#ifndef NLOHMANN_JSON_HPP
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#define NLOHMANN_JSON_HPP
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#include <algorithm> // all_of, for_each, transform
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#include <array> // array
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#include <cassert> // assert
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#include <cctype> // isdigit
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#include <ciso646> // and, not, or
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#include <cmath> // isfinite, ldexp, signbit
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#include <cstddef> // nullptr_t, ptrdiff_t, size_t
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#include <cstdint> // int64_t, uint64_t
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#include <cstdlib> // strtod, strtof, strtold, strtoul
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#include <cstring> // strlen
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#include <functional> // function, hash, less
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#include <initializer_list> // initializer_list
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#include <iomanip> // setw
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#include <iostream> // istream, ostream
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#include <iterator> // advance, begin, bidirectional_iterator_tag, distance, end, inserter, iterator, iterator_traits, next, random_access_iterator_tag, reverse_iterator
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#include <limits> // numeric_limits
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#include <locale> // locale
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#include <map> // map
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#include <memory> // addressof, allocator, allocator_traits, unique_ptr
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#include <numeric> // accumulate
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#include <sstream> // stringstream
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#include <stdexcept> // domain_error, invalid_argument, out_of_range
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#include <string> // getline, stoi, string, to_string
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#include <type_traits> // add_pointer, enable_if, is_arithmetic, is_base_of, is_const, is_constructible, is_convertible, is_floating_point, is_integral, is_nothrow_move_assignable, std::is_nothrow_move_constructible, std::is_pointer, std::is_reference, std::is_same, remove_const, remove_pointer, remove_reference
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#include <utility> // declval, forward, make_pair, move, pair, swap
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#include <vector> // vector
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// exclude unsupported compilers
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#if defined(__clang__)
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#define CLANG_VERSION (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__)
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#if CLANG_VERSION < 30400
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#error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers"
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#endif
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#elif defined(__GNUC__)
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#define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
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#if GCC_VERSION < 40900
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#error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers"
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#endif
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#endif
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// disable float-equal warnings on GCC/clang
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#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
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#pragma GCC diagnostic push
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#pragma GCC diagnostic ignored "-Wfloat-equal"
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#endif
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// disable documentation warnings on clang
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#if defined(__clang__)
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#pragma GCC diagnostic push
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#pragma GCC diagnostic ignored "-Wdocumentation"
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#endif
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// allow for portable deprecation warnings
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#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
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#define JSON_DEPRECATED __attribute__((deprecated))
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#elif defined(_MSC_VER)
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#define JSON_DEPRECATED __declspec(deprecated)
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#else
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#define JSON_DEPRECATED
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#endif
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/*!
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@brief namespace for Niels Lohmann
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@see https://github.com/nlohmann
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@since version 1.0.0
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*/
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namespace nlohmann
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{
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/*!
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@brief unnamed namespace with internal helper functions
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@since version 1.0.0
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*/
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namespace
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{
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/*!
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@brief Helper to determine whether there's a key_type for T.
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Thus helper is used to tell associative containers apart from other containers
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such as sequence containers. For instance, `std::map` passes the test as it
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contains a `mapped_type`, whereas `std::vector` fails the test.
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@sa http://stackoverflow.com/a/7728728/266378
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@since version 1.0.0, overworked in version 2.0.6
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*/
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template<typename T>
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struct has_mapped_type
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{
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private:
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template <typename U, typename = typename U::mapped_type>
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static int detect(U&&);
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static void detect(...);
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public:
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static constexpr bool value =
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std::is_integral<decltype(detect(std::declval<T>()))>::value;
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};
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}
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/*!
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@brief a class to store JSON values
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@tparam ObjectType type for JSON objects (`std::map` by default; will be used
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in @ref object_t)
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@tparam ArrayType type for JSON arrays (`std::vector` by default; will be used
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in @ref array_t)
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@tparam StringType type for JSON strings and object keys (`std::string` by
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default; will be used in @ref string_t)
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@tparam BooleanType type for JSON booleans (`bool` by default; will be used
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in @ref boolean_t)
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@tparam NumberIntegerType type for JSON integer numbers (`int64_t` by
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default; will be used in @ref number_integer_t)
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@tparam NumberUnsignedType type for JSON unsigned integer numbers (@c
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`uint64_t` by default; will be used in @ref number_unsigned_t)
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@tparam NumberFloatType type for JSON floating-point numbers (`double` by
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default; will be used in @ref number_float_t)
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@tparam AllocatorType type of the allocator to use (`std::allocator` by
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default)
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@requirement The class satisfies the following concept requirements:
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- Basic
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- [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible):
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JSON values can be default constructed. The result will be a JSON null value.
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- [MoveConstructible](http://en.cppreference.com/w/cpp/concept/MoveConstructible):
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A JSON value can be constructed from an rvalue argument.
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- [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible):
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A JSON value can be copy-constructed from an lvalue expression.
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- [MoveAssignable](http://en.cppreference.com/w/cpp/concept/MoveAssignable):
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A JSON value van be assigned from an rvalue argument.
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- [CopyAssignable](http://en.cppreference.com/w/cpp/concept/CopyAssignable):
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A JSON value can be copy-assigned from an lvalue expression.
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- [Destructible](http://en.cppreference.com/w/cpp/concept/Destructible):
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JSON values can be destructed.
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- Layout
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- [StandardLayoutType](http://en.cppreference.com/w/cpp/concept/StandardLayoutType):
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JSON values have
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[standard layout](http://en.cppreference.com/w/cpp/language/data_members#Standard_layout):
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All non-static data members are private and standard layout types, the class
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has no virtual functions or (virtual) base classes.
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- Library-wide
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- [EqualityComparable](http://en.cppreference.com/w/cpp/concept/EqualityComparable):
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JSON values can be compared with `==`, see @ref
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operator==(const_reference,const_reference).
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- [LessThanComparable](http://en.cppreference.com/w/cpp/concept/LessThanComparable):
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JSON values can be compared with `<`, see @ref
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operator<(const_reference,const_reference).
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- [Swappable](http://en.cppreference.com/w/cpp/concept/Swappable):
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Any JSON lvalue or rvalue of can be swapped with any lvalue or rvalue of
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other compatible types, using unqualified function call @ref swap().
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- [NullablePointer](http://en.cppreference.com/w/cpp/concept/NullablePointer):
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JSON values can be compared against `std::nullptr_t` objects which are used
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to model the `null` value.
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- Container
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- [Container](http://en.cppreference.com/w/cpp/concept/Container):
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JSON values can be used like STL containers and provide iterator access.
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- [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer);
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JSON values can be used like STL containers and provide reverse iterator
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access.
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@invariant The member variables @a m_value and @a m_type have the following
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relationship:
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- If `m_type == value_t::object`, then `m_value.object != nullptr`.
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- If `m_type == value_t::array`, then `m_value.array != nullptr`.
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- If `m_type == value_t::string`, then `m_value.string != nullptr`.
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The invariants are checked by member function assert_invariant().
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@internal
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@note ObjectType trick from http://stackoverflow.com/a/9860911
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@endinternal
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@see [RFC 7159: The JavaScript Object Notation (JSON) Data Interchange
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Format](http://rfc7159.net/rfc7159)
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@since version 1.0.0
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@nosubgrouping
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*/
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template <
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template<typename U, typename V, typename... Args> class ObjectType = std::map,
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template<typename U, typename... Args> class ArrayType = std::vector,
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class StringType = std::string,
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class BooleanType = bool,
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class NumberIntegerType = std::int64_t,
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class NumberUnsignedType = std::uint64_t,
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class NumberFloatType = double,
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template<typename U> class AllocatorType = std::allocator
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>
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class basic_json
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{
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private:
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/// workaround type for MSVC
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using basic_json_t = basic_json<ObjectType, ArrayType, StringType,
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BooleanType, NumberIntegerType, NumberUnsignedType, NumberFloatType,
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AllocatorType>;
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public:
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// forward declarations
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template<typename Base> class json_reverse_iterator;
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class json_pointer;
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/////////////////////
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// container types //
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/////////////////////
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/// @name container types
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/// The canonic container types to use @ref basic_json like any other STL
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/// container.
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/// @{
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/// the type of elements in a basic_json container
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using value_type = basic_json;
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/// the type of an element reference
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using reference = value_type&;
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/// the type of an element const reference
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using const_reference = const value_type&;
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/// a type to represent differences between iterators
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using difference_type = std::ptrdiff_t;
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/// a type to represent container sizes
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using size_type = std::size_t;
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/// the allocator type
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using allocator_type = AllocatorType<basic_json>;
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/// the type of an element pointer
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using pointer = typename std::allocator_traits<allocator_type>::pointer;
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/// the type of an element const pointer
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using const_pointer = typename std::allocator_traits<allocator_type>::const_pointer;
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/// an iterator for a basic_json container
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class iterator;
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/// a const iterator for a basic_json container
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class const_iterator;
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/// a reverse iterator for a basic_json container
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using reverse_iterator = json_reverse_iterator<typename basic_json::iterator>;
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/// a const reverse iterator for a basic_json container
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using const_reverse_iterator = json_reverse_iterator<typename basic_json::const_iterator>;
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/// @}
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/*!
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@brief returns the allocator associated with the container
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*/
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static allocator_type get_allocator()
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{
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return allocator_type();
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}
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///////////////////////////
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// JSON value data types //
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///////////////////////////
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/// @name JSON value data types
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/// The data types to store a JSON value. These types are derived from
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/// the template arguments passed to class @ref basic_json.
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/// @{
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/*!
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@brief a type for an object
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[RFC 7159](http://rfc7159.net/rfc7159) describes JSON objects as follows:
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> An object is an unordered collection of zero or more name/value pairs,
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> where a name is a string and a value is a string, number, boolean, null,
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> object, or array.
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To store objects in C++, a type is defined by the template parameters
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described below.
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@tparam ObjectType the container to store objects (e.g., `std::map` or
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`std::unordered_map`)
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@tparam StringType the type of the keys or names (e.g., `std::string`).
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The comparison function `std::less<StringType>` is used to order elements
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inside the container.
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@tparam AllocatorType the allocator to use for objects (e.g.,
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`std::allocator`)
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#### Default type
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With the default values for @a ObjectType (`std::map`), @a StringType
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(`std::string`), and @a AllocatorType (`std::allocator`), the default
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value for @a object_t is:
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@code {.cpp}
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std::map<
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std::string, // key_type
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basic_json, // value_type
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std::less<std::string>, // key_compare
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std::allocator<std::pair<const std::string, basic_json>> // allocator_type
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>
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@endcode
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#### Behavior
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The choice of @a object_t influences the behavior of the JSON class. With
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the default type, objects have the following behavior:
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- When all names are unique, objects will be interoperable in the sense
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that all software implementations receiving that object will agree on
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the name-value mappings.
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- When the names within an object are not unique, later stored name/value
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pairs overwrite previously stored name/value pairs, leaving the used
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names unique. For instance, `{"key": 1}` and `{"key": 2, "key": 1}` will
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be treated as equal and both stored as `{"key": 1}`.
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- Internally, name/value pairs are stored in lexicographical order of the
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names. Objects will also be serialized (see @ref dump) in this order.
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For instance, `{"b": 1, "a": 2}` and `{"a": 2, "b": 1}` will be stored
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and serialized as `{"a": 2, "b": 1}`.
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- When comparing objects, the order of the name/value pairs is irrelevant.
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This makes objects interoperable in the sense that they will not be
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affected by these differences. For instance, `{"b": 1, "a": 2}` and
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`{"a": 2, "b": 1}` will be treated as equal.
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#### Limits
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[RFC 7159](http://rfc7159.net/rfc7159) specifies:
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> An implementation may set limits on the maximum depth of nesting.
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In this class, the object's limit of nesting is not constraint explicitly.
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However, a maximum depth of nesting may be introduced by the compiler or
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runtime environment. A theoretical limit can be queried by calling the
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@ref max_size function of a JSON object.
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#### Storage
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Objects are stored as pointers in a @ref basic_json type. That is, for any
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access to object values, a pointer of type `object_t*` must be
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dereferenced.
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@sa @ref array_t -- type for an array value
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@since version 1.0.0
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@note The order name/value pairs are added to the object is *not*
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preserved by the library. Therefore, iterating an object may return
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name/value pairs in a different order than they were originally stored. In
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fact, keys will be traversed in alphabetical order as `std::map` with
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`std::less` is used by default. Please note this behavior conforms to [RFC
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7159](http://rfc7159.net/rfc7159), because any order implements the
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specified "unordered" nature of JSON objects.
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*/
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using object_t = ObjectType<StringType,
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basic_json,
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std::less<StringType>,
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AllocatorType<std::pair<const StringType,
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basic_json>>>;
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/*!
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@brief a type for an array
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[RFC 7159](http://rfc7159.net/rfc7159) describes JSON arrays as follows:
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> An array is an ordered sequence of zero or more values.
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|
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To store objects in C++, a type is defined by the template parameters
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explained below.
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@tparam ArrayType container type to store arrays (e.g., `std::vector` or
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`std::list`)
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@tparam AllocatorType allocator to use for arrays (e.g., `std::allocator`)
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#### Default type
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With the default values for @a ArrayType (`std::vector`) and @a
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AllocatorType (`std::allocator`), the default value for @a array_t is:
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@code {.cpp}
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std::vector<
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basic_json, // value_type
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std::allocator<basic_json> // allocator_type
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>
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@endcode
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#### Limits
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|
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|
[RFC 7159](http://rfc7159.net/rfc7159) specifies:
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> An implementation may set limits on the maximum depth of nesting.
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|
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In this class, the array's limit of nesting is not constraint explicitly.
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However, a maximum depth of nesting may be introduced by the compiler or
|
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runtime environment. A theoretical limit can be queried by calling the
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@ref max_size function of a JSON array.
|
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#### Storage
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Arrays are stored as pointers in a @ref basic_json type. That is, for any
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access to array values, a pointer of type `array_t*` must be dereferenced.
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@sa @ref object_t -- type for an object value
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@since version 1.0.0
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*/
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using array_t = ArrayType<basic_json, AllocatorType<basic_json>>;
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/*!
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@brief a type for a string
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|
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|
[RFC 7159](http://rfc7159.net/rfc7159) describes JSON strings as follows:
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> A string is a sequence of zero or more Unicode characters.
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To store objects in C++, a type is defined by the template parameter
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described below. Unicode values are split by the JSON class into
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byte-sized characters during deserialization.
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@tparam StringType the container to store strings (e.g., `std::string`).
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Note this container is used for keys/names in objects, see @ref object_t.
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#### Default type
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With the default values for @a StringType (`std::string`), the default
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value for @a string_t is:
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@code {.cpp}
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std::string
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@endcode
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#### String comparison
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[RFC 7159](http://rfc7159.net/rfc7159) states:
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> Software implementations are typically required to test names of object
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> members for equality. Implementations that transform the textual
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> representation into sequences of Unicode code units and then perform the
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> comparison numerically, code unit by code unit, are interoperable in the
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> sense that implementations will agree in all cases on equality or
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> inequality of two strings. For example, implementations that compare
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> strings with escaped characters unconverted may incorrectly find that
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> `"a\\b"` and `"a\u005Cb"` are not equal.
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This implementation is interoperable as it does compare strings code unit
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by code unit.
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#### Storage
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String values are stored as pointers in a @ref basic_json type. That is,
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for any access to string values, a pointer of type `string_t*` must be
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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;
|
|
|
|
/// @}
|
|
|
|
|
|
///////////////////////////
|
|
// 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 is_null(), @ref
|
|
is_object(), @ref is_array(), @ref is_string(), @ref is_boolean(), @ref
|
|
is_number() (with @ref is_number_integer(), @ref is_number_unsigned(), and
|
|
@ref is_number_float()), @ref is_discarded(), @ref is_primitive(), and
|
|
@ref is_structured() rely on it.
|
|
|
|
@note There are three enumeration entries (number_integer,
|
|
number_unsigned, and number_float), because the library distinguishes
|
|
these three types for numbers: @ref number_unsigned_t is used for unsigned
|
|
integers, @ref number_integer_t is used for signed integers, and @ref
|
|
number_float_t is used for floating-point numbers or to approximate
|
|
integers which do not fit in the limits of their respective type.
|
|
|
|
@sa @ref 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
|
|
};
|
|
|
|
|
|
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.get() != 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;
|
|
}
|
|
|
|
default:
|
|
{
|
|
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}
|
|
|
|
@sa @ref basic_json(std::nullptr_t) -- create a `null` value
|
|
@sa @ref basic_json(boolean_t value) -- create a boolean value
|
|
@sa @ref basic_json(const string_t&) -- create a string value
|
|
@sa @ref basic_json(const object_t&) -- create a object value
|
|
@sa @ref basic_json(const array_t&) -- create a array value
|
|
@sa @ref basic_json(const number_float_t) -- create a number
|
|
(floating-point) value
|
|
@sa @ref basic_json(const number_integer_t) -- create a number (integer)
|
|
value
|
|
@sa @ref basic_json(const number_unsigned_t) -- create a number (unsigned)
|
|
value
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
basic_json(const value_t value_type)
|
|
: 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 an object (explicit)
|
|
|
|
Create an object JSON value with a given content.
|
|
|
|
@param[in] val a value for the object
|
|
|
|
@complexity Linear in the size of the passed @a val.
|
|
|
|
@throw std::bad_alloc if allocation for object value fails
|
|
|
|
@liveexample{The following code shows the constructor with an @ref
|
|
object_t parameter.,basic_json__object_t}
|
|
|
|
@sa @ref basic_json(const CompatibleObjectType&) -- create an object value
|
|
from a compatible STL container
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
basic_json(const object_t& val)
|
|
: m_type(value_t::object), m_value(val)
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an object (implicit)
|
|
|
|
Create an object JSON value with a given content. This constructor allows
|
|
any type @a CompatibleObjectType that can be used to construct values of
|
|
type @ref object_t.
|
|
|
|
@tparam CompatibleObjectType An object type whose `key_type` and
|
|
`value_type` is compatible to @ref object_t. Examples include `std::map`,
|
|
`std::unordered_map`, `std::multimap`, and `std::unordered_multimap` with
|
|
a `key_type` of `std::string`, and a `value_type` from which a @ref
|
|
basic_json value can be constructed.
|
|
|
|
@param[in] val a value for the object
|
|
|
|
@complexity Linear in the size of the passed @a val.
|
|
|
|
@throw std::bad_alloc if allocation for object value fails
|
|
|
|
@liveexample{The following code shows the constructor with several
|
|
compatible object type parameters.,basic_json__CompatibleObjectType}
|
|
|
|
@sa @ref basic_json(const object_t&) -- create an object value
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
template<class CompatibleObjectType, typename std::enable_if<
|
|
std::is_constructible<typename object_t::key_type, typename CompatibleObjectType::key_type>::value and
|
|
std::is_constructible<basic_json, typename CompatibleObjectType::mapped_type>::value, int>::type = 0>
|
|
basic_json(const CompatibleObjectType& val)
|
|
: m_type(value_t::object)
|
|
{
|
|
using std::begin;
|
|
using std::end;
|
|
m_value.object = create<object_t>(begin(val), end(val));
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an array (explicit)
|
|
|
|
Create an array JSON value with a given content.
|
|
|
|
@param[in] val a value for the array
|
|
|
|
@complexity Linear in the size of the passed @a val.
|
|
|
|
@throw std::bad_alloc if allocation for array value fails
|
|
|
|
@liveexample{The following code shows the constructor with an @ref array_t
|
|
parameter.,basic_json__array_t}
|
|
|
|
@sa @ref basic_json(const CompatibleArrayType&) -- create an array value
|
|
from a compatible STL containers
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
basic_json(const array_t& val)
|
|
: m_type(value_t::array), m_value(val)
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an array (implicit)
|
|
|
|
Create an array JSON value with a given content. This constructor allows
|
|
any type @a CompatibleArrayType that can be used to construct values of
|
|
type @ref array_t.
|
|
|
|
@tparam CompatibleArrayType An object type whose `value_type` is
|
|
compatible to @ref array_t. Examples include `std::vector`, `std::deque`,
|
|
`std::list`, `std::forward_list`, `std::array`, `std::set`,
|
|
`std::unordered_set`, `std::multiset`, and `unordered_multiset` with a
|
|
`value_type` from which a @ref basic_json value can be constructed.
|
|
|
|
@param[in] val a value for the array
|
|
|
|
@complexity Linear in the size of the passed @a val.
|
|
|
|
@throw std::bad_alloc if allocation for array value fails
|
|
|
|
@liveexample{The following code shows the constructor with several
|
|
compatible array type parameters.,basic_json__CompatibleArrayType}
|
|
|
|
@sa @ref basic_json(const array_t&) -- create an array value
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
template<class CompatibleArrayType, typename std::enable_if<
|
|
not std::is_same<CompatibleArrayType, typename basic_json_t::iterator>::value and
|
|
not std::is_same<CompatibleArrayType, typename basic_json_t::const_iterator>::value and
|
|
not std::is_same<CompatibleArrayType, typename basic_json_t::reverse_iterator>::value and
|
|
not std::is_same<CompatibleArrayType, typename basic_json_t::const_reverse_iterator>::value and
|
|
not std::is_same<CompatibleArrayType, typename array_t::iterator>::value and
|
|
not std::is_same<CompatibleArrayType, typename array_t::const_iterator>::value and
|
|
std::is_constructible<basic_json, typename CompatibleArrayType::value_type>::value, int>::type = 0>
|
|
basic_json(const CompatibleArrayType& val)
|
|
: m_type(value_t::array)
|
|
{
|
|
using std::begin;
|
|
using std::end;
|
|
m_value.array = create<array_t>(begin(val), end(val));
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create a string (explicit)
|
|
|
|
Create an string JSON value with a given content.
|
|
|
|
@param[in] val a value for the string
|
|
|
|
@complexity Linear in the size of the passed @a val.
|
|
|
|
@throw std::bad_alloc if allocation for string value fails
|
|
|
|
@liveexample{The following code shows the constructor with an @ref
|
|
string_t parameter.,basic_json__string_t}
|
|
|
|
@sa @ref basic_json(const typename string_t::value_type*) -- create a
|
|
string value from a character pointer
|
|
@sa @ref basic_json(const CompatibleStringType&) -- create a string value
|
|
from a compatible string container
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
basic_json(const string_t& val)
|
|
: m_type(value_t::string), m_value(val)
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create a string (explicit)
|
|
|
|
Create a string JSON value with a given content.
|
|
|
|
@param[in] val a literal value for the string
|
|
|
|
@complexity Linear in the size of the passed @a val.
|
|
|
|
@throw std::bad_alloc if allocation for string value fails
|
|
|
|
@liveexample{The following code shows the constructor with string literal
|
|
parameter.,basic_json__string_t_value_type}
|
|
|
|
@sa @ref basic_json(const string_t&) -- create a string value
|
|
@sa @ref basic_json(const CompatibleStringType&) -- create a string value
|
|
from a compatible string container
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
basic_json(const typename string_t::value_type* val)
|
|
: basic_json(string_t(val))
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create a string (implicit)
|
|
|
|
Create a string JSON value with a given content.
|
|
|
|
@param[in] val a value for the string
|
|
|
|
@tparam CompatibleStringType an string type which is compatible to @ref
|
|
string_t, for instance `std::string`.
|
|
|
|
@complexity Linear in the size of the passed @a val.
|
|
|
|
@throw std::bad_alloc if allocation for string value fails
|
|
|
|
@liveexample{The following code shows the construction of a string value
|
|
from a compatible type.,basic_json__CompatibleStringType}
|
|
|
|
@sa @ref basic_json(const string_t&) -- create a string value
|
|
@sa @ref basic_json(const typename string_t::value_type*) -- create a
|
|
string value from a character pointer
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
template<class CompatibleStringType, typename std::enable_if<
|
|
std::is_constructible<string_t, CompatibleStringType>::value, int>::type = 0>
|
|
basic_json(const CompatibleStringType& val)
|
|
: basic_json(string_t(val))
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create a boolean (explicit)
|
|
|
|
Creates a JSON boolean type from a given value.
|
|
|
|
@param[in] val a boolean value to store
|
|
|
|
@complexity Constant.
|
|
|
|
@liveexample{The example below demonstrates boolean
|
|
values.,basic_json__boolean_t}
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
basic_json(boolean_t val) noexcept
|
|
: m_type(value_t::boolean), m_value(val)
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an integer number (explicit)
|
|
|
|
Create an integer number JSON value with a given content.
|
|
|
|
@tparam T A helper type to remove this function via SFINAE in case @ref
|
|
number_integer_t is the same as `int`. In this case, this constructor
|
|
would have the same signature as @ref basic_json(const int value). Note
|
|
the helper type @a T is not visible in this constructor's interface.
|
|
|
|
@param[in] val an integer to create a JSON number from
|
|
|
|
@complexity Constant.
|
|
|
|
@liveexample{The example below shows the construction of an integer
|
|
number value.,basic_json__number_integer_t}
|
|
|
|
@sa @ref basic_json(const int) -- create a number value (integer)
|
|
@sa @ref basic_json(const CompatibleNumberIntegerType) -- create a number
|
|
value (integer) from a compatible number type
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
template<typename T, typename std::enable_if<
|
|
not (std::is_same<T, int>::value) and
|
|
std::is_same<T, number_integer_t>::value, int>::type = 0>
|
|
basic_json(const number_integer_t val) noexcept
|
|
: m_type(value_t::number_integer), m_value(val)
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an integer number from an enum type (explicit)
|
|
|
|
Create an integer number JSON value with a given content.
|
|
|
|
@param[in] val an integer to create a JSON number from
|
|
|
|
@note This constructor allows to pass enums directly to a constructor. As
|
|
C++ has no way of specifying the type of an anonymous enum explicitly, we
|
|
can only rely on the fact that such values implicitly convert to int. As
|
|
int may already be the same type of number_integer_t, we may need to
|
|
switch off the constructor @ref basic_json(const number_integer_t).
|
|
|
|
@complexity Constant.
|
|
|
|
@liveexample{The example below shows the construction of an integer
|
|
number value from an anonymous enum.,basic_json__const_int}
|
|
|
|
@sa @ref basic_json(const number_integer_t) -- create a number value
|
|
(integer)
|
|
@sa @ref basic_json(const CompatibleNumberIntegerType) -- create a number
|
|
value (integer) from a compatible number type
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
basic_json(const int val) noexcept
|
|
: m_type(value_t::number_integer),
|
|
m_value(static_cast<number_integer_t>(val))
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an integer number (implicit)
|
|
|
|
Create an integer number JSON value with a given content. This constructor
|
|
allows any type @a CompatibleNumberIntegerType that can be used to
|
|
construct values of type @ref number_integer_t.
|
|
|
|
@tparam CompatibleNumberIntegerType An integer type which is compatible to
|
|
@ref number_integer_t. Examples include the types `int`, `int32_t`,
|
|
`long`, and `short`.
|
|
|
|
@param[in] val an integer to create a JSON number from
|
|
|
|
@complexity Constant.
|
|
|
|
@liveexample{The example below shows the construction of several integer
|
|
number values from compatible
|
|
types.,basic_json__CompatibleIntegerNumberType}
|
|
|
|
@sa @ref basic_json(const number_integer_t) -- create a number value
|
|
(integer)
|
|
@sa @ref basic_json(const int) -- create a number value (integer)
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
template<typename CompatibleNumberIntegerType, typename std::enable_if<
|
|
std::is_constructible<number_integer_t, CompatibleNumberIntegerType>::value and
|
|
std::numeric_limits<CompatibleNumberIntegerType>::is_integer and
|
|
std::numeric_limits<CompatibleNumberIntegerType>::is_signed,
|
|
CompatibleNumberIntegerType>::type = 0>
|
|
basic_json(const CompatibleNumberIntegerType val) noexcept
|
|
: m_type(value_t::number_integer),
|
|
m_value(static_cast<number_integer_t>(val))
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an unsigned integer number (explicit)
|
|
|
|
Create an unsigned integer number JSON value with a given content.
|
|
|
|
@tparam T helper type to compare number_unsigned_t and unsigned int (not
|
|
visible in) the interface.
|
|
|
|
@param[in] val an integer to create a JSON number from
|
|
|
|
@complexity Constant.
|
|
|
|
@sa @ref basic_json(const CompatibleNumberUnsignedType) -- create a number
|
|
value (unsigned integer) from a compatible number type
|
|
|
|
@since version 2.0.0
|
|
*/
|
|
template<typename T, typename std::enable_if<
|
|
not (std::is_same<T, int>::value) and
|
|
std::is_same<T, number_unsigned_t>::value, int>::type = 0>
|
|
basic_json(const number_unsigned_t val) noexcept
|
|
: m_type(value_t::number_unsigned), m_value(val)
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an unsigned number (implicit)
|
|
|
|
Create an unsigned number JSON value with a given content. This
|
|
constructor allows any type @a CompatibleNumberUnsignedType that can be
|
|
used to construct values of type @ref number_unsigned_t.
|
|
|
|
@tparam CompatibleNumberUnsignedType An integer type which is compatible
|
|
to @ref number_unsigned_t. Examples may include the types `unsigned int`,
|
|
`uint32_t`, or `unsigned short`.
|
|
|
|
@param[in] val an unsigned integer to create a JSON number from
|
|
|
|
@complexity Constant.
|
|
|
|
@sa @ref basic_json(const number_unsigned_t) -- create a number value
|
|
(unsigned)
|
|
|
|
@since version 2.0.0
|
|
*/
|
|
template<typename CompatibleNumberUnsignedType, typename std::enable_if <
|
|
std::is_constructible<number_unsigned_t, CompatibleNumberUnsignedType>::value and
|
|
std::numeric_limits<CompatibleNumberUnsignedType>::is_integer and
|
|
not std::numeric_limits<CompatibleNumberUnsignedType>::is_signed,
|
|
CompatibleNumberUnsignedType>::type = 0>
|
|
basic_json(const CompatibleNumberUnsignedType val) noexcept
|
|
: m_type(value_t::number_unsigned),
|
|
m_value(static_cast<number_unsigned_t>(val))
|
|
{
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create a floating-point number (explicit)
|
|
|
|
Create a floating-point number JSON value with a given content.
|
|
|
|
@param[in] val a floating-point value to create a JSON number from
|
|
|
|
@note [RFC 7159](http://www.rfc-editor.org/rfc/rfc7159.txt), section 6
|
|
disallows NaN values:
|
|
> Numeric values that cannot be represented in the grammar below (such as
|
|
> Infinity and NaN) are not permitted.
|
|
In case the parameter @a val is not a number, a JSON null value is created
|
|
instead.
|
|
|
|
@complexity Constant.
|
|
|
|
@liveexample{The following example creates several floating-point
|
|
values.,basic_json__number_float_t}
|
|
|
|
@sa @ref basic_json(const CompatibleNumberFloatType) -- create a number
|
|
value (floating-point) from a compatible number type
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
basic_json(const number_float_t val) noexcept
|
|
: m_type(value_t::number_float), m_value(val)
|
|
{
|
|
// replace infinity and NAN by null
|
|
if (not std::isfinite(val))
|
|
{
|
|
m_type = value_t::null;
|
|
m_value = json_value();
|
|
}
|
|
|
|
assert_invariant();
|
|
}
|
|
|
|
/*!
|
|
@brief create an floating-point number (implicit)
|
|
|
|
Create an floating-point number JSON value with a given content. This
|
|
constructor allows any type @a CompatibleNumberFloatType that can be used
|
|
to construct values of type @ref number_float_t.
|
|
|
|
@tparam CompatibleNumberFloatType A floating-point type which is
|
|
compatible to @ref number_float_t. Examples may include the types `float`
|
|
or `double`.
|
|
|
|
@param[in] val a floating-point to create a JSON number from
|
|
|
|
@note [RFC 7159](http://www.rfc-editor.org/rfc/rfc7159.txt), section 6
|
|
disallows NaN values:
|
|
> Numeric values that cannot be represented in the grammar below (such as
|
|
> Infinity and NaN) are not permitted.
|
|
In case the parameter @a val is not a number, a JSON null value is
|
|
created instead.
|
|
|
|
@complexity Constant.
|
|
|
|
@liveexample{The example below shows the construction of several
|
|
floating-point number values from compatible
|
|
types.,basic_json__CompatibleNumberFloatType}
|
|
|
|
@sa @ref basic_json(const number_float_t) -- create a number value
|
|
(floating-point)
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
template<typename CompatibleNumberFloatType, typename = typename std::enable_if<
|
|
std::is_constructible<number_float_t, CompatibleNumberFloatType>::value and
|
|
std::is_floating_point<CompatibleNumberFloatType>::value>::type>
|
|
basic_json(const CompatibleNumberFloatType val) noexcept
|
|
: basic_json(number_float_t(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)
|
|
{
|
|
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)
|
|
{
|
|
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())
|
|
{
|
|
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:
|
|
{
|
|
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;
|
|
// fix locale problems
|
|
ss.imbue(std::locale::classic());
|
|
|
|
// 6, 15 or 16 digits of precision allows round-trip IEEE 754
|
|
// string->float->string, string->double->string or string->long
|
|
// double->string; to be safe, we read this value from
|
|
// std::numeric_limits<number_float_t>::digits10
|
|
ss.precision(std::numeric_limits<double>::digits10);
|
|
|
|
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 an object (explicit)
|
|
template<class T, typename std::enable_if<
|
|
std::is_convertible<typename object_t::key_type, typename T::key_type>::value and
|
|
std::is_convertible<basic_json_t, typename T::mapped_type>::value, int>::type = 0>
|
|
T get_impl(T*) const
|
|
{
|
|
if (is_object())
|
|
{
|
|
return T(m_value.object->begin(), m_value.object->end());
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("type must be object, but is " + type_name());
|
|
}
|
|
}
|
|
|
|
/// get an object (explicit)
|
|
object_t get_impl(object_t*) const
|
|
{
|
|
if (is_object())
|
|
{
|
|
return *(m_value.object);
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("type must be object, but is " + type_name());
|
|
}
|
|
}
|
|
|
|
/// get an array (explicit)
|
|
template<class T, typename std::enable_if<
|
|
std::is_convertible<basic_json_t, typename T::value_type>::value and
|
|
not std::is_same<basic_json_t, typename T::value_type>::value and
|
|
not std::is_arithmetic<T>::value and
|
|
not std::is_convertible<std::string, T>::value and
|
|
not has_mapped_type<T>::value, int>::type = 0>
|
|
T get_impl(T*) const
|
|
{
|
|
if (is_array())
|
|
{
|
|
T to_vector;
|
|
std::transform(m_value.array->begin(), m_value.array->end(),
|
|
std::inserter(to_vector, to_vector.end()), [](basic_json i)
|
|
{
|
|
return i.get<typename T::value_type>();
|
|
});
|
|
return to_vector;
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("type must be array, but is " + type_name());
|
|
}
|
|
}
|
|
|
|
/// get an array (explicit)
|
|
template<class T, typename std::enable_if<
|
|
std::is_convertible<basic_json_t, T>::value and
|
|
not std::is_same<basic_json_t, T>::value, int>::type = 0>
|
|
std::vector<T> get_impl(std::vector<T>*) const
|
|
{
|
|
if (is_array())
|
|
{
|
|
std::vector<T> to_vector;
|
|
to_vector.reserve(m_value.array->size());
|
|
std::transform(m_value.array->begin(), m_value.array->end(),
|
|
std::inserter(to_vector, to_vector.end()), [](basic_json i)
|
|
{
|
|
return i.get<T>();
|
|
});
|
|
return to_vector;
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("type must be array, but is " + type_name());
|
|
}
|
|
}
|
|
|
|
/// get an array (explicit)
|
|
template<class T, typename std::enable_if<
|
|
std::is_same<basic_json, typename T::value_type>::value and
|
|
not has_mapped_type<T>::value, int>::type = 0>
|
|
T get_impl(T*) const
|
|
{
|
|
if (is_array())
|
|
{
|
|
return T(m_value.array->begin(), m_value.array->end());
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("type must be array, but is " + type_name());
|
|
}
|
|
}
|
|
|
|
/// get an array (explicit)
|
|
array_t get_impl(array_t*) const
|
|
{
|
|
if (is_array())
|
|
{
|
|
return *(m_value.array);
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("type must be array, but is " + type_name());
|
|
}
|
|
}
|
|
|
|
/// get a string (explicit)
|
|
template<typename T, typename std::enable_if<
|
|
std::is_convertible<string_t, T>::value, int>::type = 0>
|
|
T get_impl(T*) const
|
|
{
|
|
if (is_string())
|
|
{
|
|
return *m_value.string;
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("type must be string, but is " + type_name());
|
|
}
|
|
}
|
|
|
|
/// get a number (explicit)
|
|
template<typename T, typename std::enable_if<
|
|
std::is_arithmetic<T>::value, int>::type = 0>
|
|
T get_impl(T*) const
|
|
{
|
|
switch (m_type)
|
|
{
|
|
case value_t::number_integer:
|
|
{
|
|
return static_cast<T>(m_value.number_integer);
|
|
}
|
|
|
|
case value_t::number_unsigned:
|
|
{
|
|
return static_cast<T>(m_value.number_unsigned);
|
|
}
|
|
|
|
case value_t::number_float:
|
|
{
|
|
return static_cast<T>(m_value.number_float);
|
|
}
|
|
|
|
default:
|
|
{
|
|
throw std::domain_error("type must be number, but is " + type_name());
|
|
}
|
|
}
|
|
}
|
|
|
|
/// get a boolean (explicit)
|
|
constexpr boolean_t get_impl(boolean_t*) const
|
|
{
|
|
return is_boolean()
|
|
? m_value.boolean
|
|
: throw std::domain_error("type must be boolean, but is " + type_name());
|
|
}
|
|
|
|
/// get a pointer to the value (object)
|
|
object_t* get_impl_ptr(object_t*) 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*) const noexcept
|
|
{
|
|
return is_object() ? m_value.object : nullptr;
|
|
}
|
|
|
|
/// get a pointer to the value (array)
|
|
array_t* get_impl_ptr(array_t*) 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*) const noexcept
|
|
{
|
|
return is_array() ? m_value.array : nullptr;
|
|
}
|
|
|
|
/// get a pointer to the value (string)
|
|
string_t* get_impl_ptr(string_t*) 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*) const noexcept
|
|
{
|
|
return is_string() ? m_value.string : nullptr;
|
|
}
|
|
|
|
/// get a pointer to the value (boolean)
|
|
boolean_t* get_impl_ptr(boolean_t*) 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*) 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*) 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*) 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*) 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*) 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*) 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*) 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;
|
|
}
|
|
else
|
|
{
|
|
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 a value (explicit)
|
|
|
|
Explicit type conversion between the JSON value and a compatible value.
|
|
|
|
@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
|
|
|
|
@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; example: `"type must be object, but is null"`
|
|
|
|
@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>`.,get__ValueType_const}
|
|
|
|
@internal
|
|
The idea of using a casted null pointer to choose the correct
|
|
implementation is from <http://stackoverflow.com/a/8315197/266378>.
|
|
@endinternal
|
|
|
|
@sa @ref operator ValueType() const for implicit conversion
|
|
@sa @ref get() for pointer-member access
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
template<typename ValueType, typename std::enable_if<
|
|
not std::is_pointer<ValueType>::value, int>::type = 0>
|
|
ValueType get() const
|
|
{
|
|
return get_impl(static_cast<ValueType*>(nullptr));
|
|
}
|
|
|
|
/*!
|
|
@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)
|
|
|
|
Implict 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<< abiguity 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())
|
|
{
|
|
try
|
|
{
|
|
return m_value.array->at(idx);
|
|
}
|
|
catch (std::out_of_range&)
|
|
{
|
|
// create better exception explanation
|
|
throw std::out_of_range("array index " + std::to_string(idx) + " is out of range");
|
|
}
|
|
}
|
|
else
|
|
{
|
|
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())
|
|
{
|
|
try
|
|
{
|
|
return m_value.array->at(idx);
|
|
}
|
|
catch (std::out_of_range&)
|
|
{
|
|
// create better exception explanation
|
|
throw std::out_of_range("array index " + std::to_string(idx) + " is out of range");
|
|
}
|
|
}
|
|
else
|
|
{
|
|
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())
|
|
{
|
|
try
|
|
{
|
|
return m_value.object->at(key);
|
|
}
|
|
catch (std::out_of_range&)
|
|
{
|
|
// create better exception explanation
|
|
throw std::out_of_range("key '" + key + "' not found");
|
|
}
|
|
}
|
|
else
|
|
{
|
|
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())
|
|
{
|
|
try
|
|
{
|
|
return m_value.object->at(key);
|
|
}
|
|
catch (std::out_of_range&)
|
|
{
|
|
// create better exception explanation
|
|
throw std::out_of_range("key '" + key + "' not found");
|
|
}
|
|
}
|
|
else
|
|
{
|
|
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);
|
|
}
|
|
else
|
|
{
|
|
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);
|
|
}
|
|
else
|
|
{
|
|
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);
|
|
}
|
|
else
|
|
{
|
|
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;
|
|
}
|
|
else
|
|
{
|
|
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);
|
|
}
|
|
else
|
|
{
|
|
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;
|
|
}
|
|
else
|
|
{
|
|
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;
|
|
}
|
|
else
|
|
{
|
|
return default_value;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
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
|
|
try
|
|
{
|
|
return ptr.get_checked(this);
|
|
}
|
|
catch (std::out_of_range&)
|
|
{
|
|
return default_value;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("cannot use value() with " + type_name());
|
|
}
|
|
}
|
|
|
|
/*!
|
|
@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 cast 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 cast 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 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)
|
|
{
|
|
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())
|
|
{
|
|
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:
|
|
{
|
|
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)
|
|
{
|
|
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())
|
|
{
|
|
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:
|
|
{
|
|
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);
|
|
}
|
|
else
|
|
{
|
|
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())
|
|
{
|
|
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
|
|
{
|
|
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.
|
|
|
|
@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, past-the-end (see 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).
|
|
|
|
@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 | `[]`
|
|
|
|
@note Floating-point numbers are set to `0.0` which will be serialized to
|
|
`0`. The vale type remains @ref number_float_t.
|
|
|
|
@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()))
|
|
{
|
|
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()))
|
|
{
|
|
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()))
|
|
{
|
|
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()))
|
|
{
|
|
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()))
|
|
{
|
|
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 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)
|
|
{
|
|
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;
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("cannot use insert() with " + type_name());
|
|
}
|
|
}
|
|
|
|
/*!
|
|
@brief inserts element
|
|
@copydoc insert(const_iterator, const basic_json&)
|
|
*/
|
|
iterator insert(const_iterator pos, basic_json&& val)
|
|
{
|
|
return insert(pos, val);
|
|
}
|
|
|
|
/*!
|
|
@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)
|
|
{
|
|
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;
|
|
}
|
|
else
|
|
{
|
|
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())
|
|
{
|
|
throw std::domain_error("cannot use insert() with " + type_name());
|
|
}
|
|
|
|
// check if iterator pos fits to this JSON value
|
|
if (pos.m_object != this)
|
|
{
|
|
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)
|
|
{
|
|
throw std::domain_error("iterators do not fit");
|
|
}
|
|
|
|
if (first.m_object == this or last.m_object == this)
|
|
{
|
|
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())
|
|
{
|
|
throw std::domain_error("cannot use insert() with " + type_name());
|
|
}
|
|
|
|
// check if iterator pos fits to this JSON value
|
|
if (pos.m_object != this)
|
|
{
|
|
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
|
|
{
|
|
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
|
|
{
|
|
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
|
|
{
|
|
throw std::domain_error("cannot use swap() with " + type_name());
|
|
}
|
|
}
|
|
|
|
/// @}
|
|
|
|
|
|
//////////////////////////////////////////
|
|
// lexicographical comparison operators //
|
|
//////////////////////////////////////////
|
|
|
|
/// @name lexicographical comparison operators
|
|
/// @{
|
|
|
|
private:
|
|
/*!
|
|
@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
|
|
*/
|
|
friend 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)];
|
|
}
|
|
|
|
public:
|
|
/*!
|
|
@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
|
|
|
|
The functions compares the given JSON value against a null pointer. As the
|
|
null pointer can be used to initialize a JSON value to null, a comparison
|
|
of JSON value @a v with a null pointer should be equivalent to call
|
|
`v.is_null()`.
|
|
|
|
@param[in] v JSON value to consider
|
|
@return whether @a v is null
|
|
|
|
@complexity Constant.
|
|
|
|
@liveexample{The example compares several JSON types to the null pointer.
|
|
,operator__equal__nullptr_t}
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
friend bool operator==(const_reference v, std::nullptr_t) noexcept
|
|
{
|
|
return v.is_null();
|
|
}
|
|
|
|
/*!
|
|
@brief comparison: equal
|
|
@copydoc operator==(const_reference, std::nullptr_t)
|
|
*/
|
|
friend bool operator==(std::nullptr_t, const_reference v) noexcept
|
|
{
|
|
return v.is_null();
|
|
}
|
|
|
|
/*!
|
|
@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
|
|
|
|
The functions compares the given JSON value against a null pointer. As the
|
|
null pointer can be used to initialize a JSON value to null, a comparison
|
|
of JSON value @a v with a null pointer should be equivalent to call
|
|
`not v.is_null()`.
|
|
|
|
@param[in] v JSON value to consider
|
|
@return whether @a v is not null
|
|
|
|
@complexity Constant.
|
|
|
|
@liveexample{The example compares several JSON types to the null pointer.
|
|
,operator__notequal__nullptr_t}
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
friend bool operator!=(const_reference v, std::nullptr_t) noexcept
|
|
{
|
|
return not v.is_null();
|
|
}
|
|
|
|
/*!
|
|
@brief comparison: not equal
|
|
@copydoc operator!=(const_reference, std::nullptr_t)
|
|
*/
|
|
friend bool operator!=(std::nullptr_t, const_reference v) noexcept
|
|
{
|
|
return not v.is_null();
|
|
}
|
|
|
|
/*!
|
|
@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)`.
|
|
|
|
@note During serializaion, the locale and the precision of the output
|
|
stream @a o are changed. The original values are restored when the
|
|
function returns.
|
|
|
|
@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);
|
|
|
|
// fix locale problems
|
|
const auto old_locale = o.imbue(std::locale::classic());
|
|
// set precision
|
|
|
|
// 6, 15 or 16 digits of precision allows round-trip IEEE 754
|
|
// string->float->string, string->double->string or string->long
|
|
// double->string; to be safe, we read this value from
|
|
// std::numeric_limits<number_float_t>::digits10
|
|
const auto old_precision = o.precision(std::numeric_limits<double>::digits10);
|
|
|
|
// do the actual serialization
|
|
j.dump(o, pretty_print, static_cast<unsigned int>(indentation));
|
|
|
|
// reset locale and precision
|
|
o.imbue(old_locale);
|
|
o.precision(old_precision);
|
|
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::make_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:
|
|
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>((number >> 070) & 0xff));
|
|
vec.push_back(static_cast<uint8_t>((number >> 060) & 0xff));
|
|
vec.push_back(static_cast<uint8_t>((number >> 050) & 0xff));
|
|
vec.push_back(static_cast<uint8_t>((number >> 040) & 0xff));
|
|
// intentional fall-through
|
|
}
|
|
|
|
case 4:
|
|
{
|
|
vec.push_back(static_cast<uint8_t>((number >> 030) & 0xff));
|
|
vec.push_back(static_cast<uint8_t>((number >> 020) & 0xff));
|
|
// intentional fall-through
|
|
}
|
|
|
|
case 2:
|
|
{
|
|
vec.push_back(static_cast<uint8_t>((number >> 010) & 0xff));
|
|
// intentional fall-through
|
|
}
|
|
|
|
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())
|
|
{
|
|
throw std::out_of_range("cannot read " + std::to_string(sizeof(T)) + " bytes from vector");
|
|
}
|
|
|
|
T result;
|
|
uint8_t* 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 <= UINT8_MAX)
|
|
{
|
|
// uint 8
|
|
v.push_back(0xcc);
|
|
add_to_vector(v, 1, j.m_value.number_unsigned);
|
|
}
|
|
else if (j.m_value.number_unsigned <= UINT16_MAX)
|
|
{
|
|
// uint 16
|
|
v.push_back(0xcd);
|
|
add_to_vector(v, 2, j.m_value.number_unsigned);
|
|
}
|
|
else if (j.m_value.number_unsigned <= UINT32_MAX)
|
|
{
|
|
// uint 32
|
|
v.push_back(0xce);
|
|
add_to_vector(v, 4, j.m_value.number_unsigned);
|
|
}
|
|
else if (j.m_value.number_unsigned <= UINT64_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 >= INT8_MIN and j.m_value.number_integer <= INT8_MAX)
|
|
{
|
|
// int 8
|
|
v.push_back(0xd0);
|
|
add_to_vector(v, 1, j.m_value.number_integer);
|
|
}
|
|
else if (j.m_value.number_integer >= INT16_MIN and j.m_value.number_integer <= INT16_MAX)
|
|
{
|
|
// int 16
|
|
v.push_back(0xd1);
|
|
add_to_vector(v, 2, j.m_value.number_integer);
|
|
}
|
|
else if (j.m_value.number_integer >= INT32_MIN and j.m_value.number_integer <= INT32_MAX)
|
|
{
|
|
// int 32
|
|
v.push_back(0xd2);
|
|
add_to_vector(v, 4, j.m_value.number_integer);
|
|
}
|
|
else if (j.m_value.number_integer >= INT64_MIN and j.m_value.number_integer <= INT64_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 <= UINT8_MAX)
|
|
{
|
|
// uint 8
|
|
v.push_back(0xcc);
|
|
add_to_vector(v, 1, j.m_value.number_unsigned);
|
|
}
|
|
else if (j.m_value.number_unsigned <= UINT16_MAX)
|
|
{
|
|
// uint 16
|
|
v.push_back(0xcd);
|
|
add_to_vector(v, 2, j.m_value.number_unsigned);
|
|
}
|
|
else if (j.m_value.number_unsigned <= UINT32_MAX)
|
|
{
|
|
// uint 32
|
|
v.push_back(0xce);
|
|
add_to_vector(v, 4, j.m_value.number_unsigned);
|
|
}
|
|
else if (j.m_value.number_unsigned <= UINT64_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 uint8_t* 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 <= UINT8_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 <= UINT16_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 <= UINT32_MAX)
|
|
{
|
|
v.push_back(0x1a);
|
|
// four-byte uint32_t
|
|
add_to_vector(v, 4, j.m_value.number_integer);
|
|
}
|
|
else if (j.m_value.number_integer <= UINT64_MAX)
|
|
{
|
|
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 <= UINT8_MAX)
|
|
{
|
|
// int 8
|
|
v.push_back(0x38);
|
|
add_to_vector(v, 1, positive_number);
|
|
}
|
|
else if (positive_number <= UINT16_MAX)
|
|
{
|
|
// int 16
|
|
v.push_back(0x39);
|
|
add_to_vector(v, 2, positive_number);
|
|
}
|
|
else if (positive_number <= UINT32_MAX)
|
|
{
|
|
// int 32
|
|
v.push_back(0x3a);
|
|
add_to_vector(v, 4, positive_number);
|
|
}
|
|
else if (positive_number <= UINT64_MAX)
|
|
{
|
|
// 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 uint8_t* 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 + 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 + 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 + 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 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)
|
|
{
|
|
// 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];
|
|
}
|
|
else 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
|
|
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[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[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 = get_from_vector<uint8_t>(v, current_idx);
|
|
const size_t offset = current_idx + 2;
|
|
idx += len + 1; // skip size byte + content bytes
|
|
return std::string(reinterpret_cast<const char*>(v.data()) + offset, len);
|
|
}
|
|
|
|
case 0xda: // str 16
|
|
{
|
|
const auto len = get_from_vector<uint16_t>(v, current_idx);
|
|
const size_t offset = current_idx + 3;
|
|
idx += len + 2; // skip 2 size bytes + content bytes
|
|
return std::string(reinterpret_cast<const char*>(v.data()) + offset, len);
|
|
}
|
|
|
|
case 0xdb: // str 32
|
|
{
|
|
const auto len = get_from_vector<uint32_t>(v, current_idx);
|
|
const size_t offset = current_idx + 5;
|
|
idx += len + 4; // skip 4 size bytes + content bytes
|
|
return std::string(reinterpret_cast<const char*>(v.data()) + offset, len);
|
|
}
|
|
|
|
case 0xdc: // array 16
|
|
{
|
|
basic_json result = value_t::array;
|
|
const auto len = 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 = 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 = 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 = 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:
|
|
{
|
|
throw std::invalid_argument("error parsing a msgpack @ " + std::to_string(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[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) - 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 size_t len = v[current_idx] - 0x60;
|
|
const size_t offset = current_idx + 1;
|
|
idx += len; // skip content bytes
|
|
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 = get_from_vector<uint8_t>(v, current_idx);
|
|
const size_t offset = current_idx + 2;
|
|
idx += len + 1; // skip size byte + content bytes
|
|
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 = get_from_vector<uint16_t>(v, current_idx);
|
|
const size_t offset = current_idx + 3;
|
|
idx += len + 2; // skip 2 size bytes + content bytes
|
|
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 = get_from_vector<uint32_t>(v, current_idx);
|
|
const size_t offset = current_idx + 5;
|
|
idx += len + 4; // skip 4 size bytes + content bytes
|
|
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 = get_from_vector<uint64_t>(v, current_idx);
|
|
const size_t offset = current_idx + 9;
|
|
idx += len + 8; // skip 8 size bytes + content bytes
|
|
return std::string(reinterpret_cast<const char*>(v.data()) + offset, len);
|
|
}
|
|
|
|
case 0x7f: // UTF-8 string (indefinite length)
|
|
{
|
|
std::string result;
|
|
while (v[idx] != 0xff)
|
|
{
|
|
string_t s = from_cbor_internal(v, idx);
|
|
result += s;
|
|
}
|
|
// skip break byte (0xFF)
|
|
idx += 1;
|
|
return result;
|
|
}
|
|
|
|
// array (0x00..0x17 data items follow)
|
|
case 0x80:
|
|
case 0x81:
|
|
case 0x82:
|
|
case 0x83:
|
|
case 0x84:
|
|
case 0x85:
|
|
case 0x86:
|
|
case 0x87:
|
|
case 0x88:
|
|
case 0x89:
|
|
case 0x8a:
|
|
case 0x8b:
|
|
case 0x8c:
|
|
case 0x8d:
|
|
case 0x8e:
|
|
case 0x8f:
|
|
case 0x90:
|
|
case 0x91:
|
|
case 0x92:
|
|
case 0x93:
|
|
case 0x94:
|
|
case 0x95:
|
|
case 0x96:
|
|
case 0x97:
|
|
{
|
|
basic_json result = value_t::array;
|
|
const size_t len = 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 = 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 = 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 = 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 = 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[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 size_t len = 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 = 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 = 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 = 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 = 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[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[current_idx + 1] << 8) + v[current_idx + 2];
|
|
const int exp = (half >> 10) & 0x1f;
|
|
const int mant = half & 0x3ff;
|
|
double val;
|
|
if (exp == 0)
|
|
{
|
|
val = std::ldexp(mant, -24);
|
|
}
|
|
else if (exp != 31)
|
|
{
|
|
val = std::ldexp(mant + 1024, exp - 25);
|
|
}
|
|
else
|
|
{
|
|
val = mant == 0 ? INFINITY : NAN;
|
|
}
|
|
return half & 0x8000 ? -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[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[current_idx + 1 + byte];
|
|
}
|
|
idx += sizeof(double); // skip content bytes
|
|
return res;
|
|
}
|
|
|
|
default: // anything else (0xFF is handled inside the other types)
|
|
{
|
|
throw std::invalid_argument("error parsing a CBOR @ " + std::to_string(current_idx) + ": " + std::to_string(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>&) for the analogous
|
|
deserialization
|
|
@sa @ref to_cbor(const basic_json& for the related CBOR format
|
|
*/
|
|
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
|
|
@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>&) for the related CBOR format
|
|
*/
|
|
static basic_json from_msgpack(const std::vector<uint8_t>& v)
|
|
{
|
|
size_t i = 0;
|
|
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>&) for the analogous
|
|
deserialization
|
|
@sa @ref to_msgpack(const basic_json& for the related MessagePack format
|
|
*/
|
|
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
|
|
@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>&) for the related
|
|
MessagePack format
|
|
*/
|
|
static basic_json from_cbor(const std::vector<uint8_t>& v)
|
|
{
|
|
size_t i = 0;
|
|
return from_cbor_internal(v, i);
|
|
}
|
|
|
|
/// @}
|
|
|
|
private:
|
|
///////////////////////////
|
|
// 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.
|
|
|
|
@since version 1.0.0
|
|
*/
|
|
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";
|
|
}
|
|
}
|
|
|
|
/*!
|
|
@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;
|
|
}
|
|
else
|
|
{
|
|
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 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 << m_value.number_integer;
|
|
return;
|
|
}
|
|
|
|
case value_t::number_unsigned:
|
|
{
|
|
o << m_value.number_unsigned;
|
|
return;
|
|
}
|
|
|
|
case value_t::number_float:
|
|
{
|
|
if (m_value.number_float == 0)
|
|
{
|
|
// special case for zero to get "0.0"/"-0.0"
|
|
o << (std::signbit(m_value.number_float) ? "-0.0" : "0.0");
|
|
}
|
|
else
|
|
{
|
|
o << m_value.number_float;
|
|
}
|
|
return;
|
|
}
|
|
|
|
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:
|
|
/// 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);
|
|
}
|
|
|
|
/// return reference to the value to change and compare
|
|
operator difference_type& () noexcept
|
|
{
|
|
return m_it;
|
|
}
|
|
|
|
/// return value to compare
|
|
constexpr operator difference_type () const noexcept
|
|
{
|
|
return m_it;
|
|
}
|
|
|
|
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
|
|
*/
|
|
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 iterator and const_iterator.
|
|
|
|
This function is only called if this class is an iterator.
|
|
If this class is a 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:
|
|
{
|
|
throw std::out_of_range("cannot get value");
|
|
}
|
|
|
|
default:
|
|
{
|
|
if (m_it.primitive_iterator.is_begin())
|
|
{
|
|
return *m_object;
|
|
}
|
|
else
|
|
{
|
|
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;
|
|
}
|
|
else
|
|
{
|
|
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)
|
|
{
|
|
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)
|
|
{
|
|
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:
|
|
{
|
|
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:
|
|
{
|
|
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:
|
|
{
|
|
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:
|
|
{
|
|
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:
|
|
{
|
|
throw std::out_of_range("cannot get value");
|
|
}
|
|
|
|
default:
|
|
{
|
|
if (m_it.primitive_iterator == -n)
|
|
{
|
|
return *m_object;
|
|
}
|
|
else
|
|
{
|
|
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;
|
|
}
|
|
else
|
|
{
|
|
throw std::domain_error("cannot use key() for non-object iterators");
|
|
}
|
|
}
|
|
|
|
/*!
|
|
@brief return the value of an iterator
|
|
@pre The iterator is initialized; i.e. `m_object != nullptr`.
|
|
*/
|
|
reference value() const
|
|
{
|
|
return operator*();
|
|
}
|
|
|
|
private:
|
|
/// associated JSON instance
|
|
pointer m_object = nullptr;
|
|
/// the actual iterator of the associated instance
|
|
internal_iterator m_it = internal_iterator();
|
|
};
|
|
|
|
/*!
|
|
@brief a 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_number, ///< a number -- use get_number() for actual value
|
|
begin_array, ///< the character for array begin `[`
|
|
begin_object, ///< the character for object begin `{`
|
|
end_array, ///< the character for array end `]`
|
|
end_object, ///< the character for object end `}`
|
|
name_separator, ///< the name separator `:`
|
|
value_separator, ///< the value separator `,`
|
|
parse_error, ///< indicating a parse error
|
|
end_of_input ///< indicating the end of the input buffer
|
|
};
|
|
|
|
/// the char type to use in the lexer
|
|
using lexer_char_t = unsigned char;
|
|
|
|
/// a lexer from a buffer with given length
|
|
lexer(const lexer_char_t* buff, const size_t len) noexcept
|
|
: m_content(buff)
|
|
{
|
|
assert(m_content != nullptr);
|
|
m_start = m_cursor = m_content;
|
|
m_limit = m_content + len;
|
|
}
|
|
|
|
/// a lexer from an input stream
|
|
explicit lexer(std::istream& s)
|
|
: m_stream(&s), m_line_buffer()
|
|
{
|
|
// immediately abort if stream is erroneous
|
|
if (s.fail())
|
|
{
|
|
throw std::invalid_argument("stream error: " + std::string(strerror(errno)));
|
|
}
|
|
|
|
// fill buffer
|
|
fill_line_buffer();
|
|
|
|
// skip UTF-8 byte-order mark
|
|
if (m_line_buffer.size() >= 3 and m_line_buffer.substr(0, 3) == "\xEF\xBB\xBF")
|
|
{
|
|
m_line_buffer[0] = ' ';
|
|
m_line_buffer[1] = ' ';
|
|
m_line_buffer[2] = ' ';
|
|
}
|
|
}
|
|
|
|
// switch off unwanted functions (due to pointer members)
|
|
lexer() = delete;
|
|
lexer(const lexer&) = delete;
|
|
lexer operator=(const lexer&) = delete;
|
|
|
|
/*!
|
|
@brief create a string from one or two Unicode code points
|
|
|
|
There are two cases: (1) @a codepoint1 is in the Basic Multilingual
|
|
Plane (U+0000 through U+FFFF) and @a codepoint2 is 0, or (2)
|
|
@a codepoint1 and @a codepoint2 are a UTF-16 surrogate pair to
|
|
represent a code point above U+FFFF.
|
|
|
|
@param[in] codepoint1 the code point (can be high surrogate)
|
|
@param[in] codepoint2 the code point (can be low surrogate or 0)
|
|
|
|
@return string representation of the code point; the length of the
|
|
result string is between 1 and 4 characters.
|
|
|
|
@throw std::out_of_range if code point is > 0x10ffff; example: `"code
|
|
points above 0x10FFFF are invalid"`
|
|
@throw std::invalid_argument if the low surrogate is invalid; example:
|
|
`""missing or wrong low surrogate""`
|
|
|
|
@complexity Constant.
|
|
|
|
@see <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
|
|
{
|
|
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
|
|
{
|
|
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 token_type::value_number:
|
|
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);
|
|
|
|
/*!re2c
|
|
re2c:define:YYCTYPE = lexer_char_t;
|
|
re2c:define:YYCURSOR = m_cursor;
|
|
re2c:define:YYLIMIT = m_limit;
|
|
re2c:define:YYMARKER = m_marker;
|
|
re2c:define:YYFILL = "fill_line_buffer(@@); // LCOV_EXCL_LINE";
|
|
re2c:define:YYFILL:naked = 1;
|
|
re2c:yyfill:enable = 1;
|
|
re2c:indent:string = " ";
|
|
re2c:indent:top = 1;
|
|
re2c:labelprefix = "basic_json_parser_";
|
|
|
|
// ignore whitespace
|
|
ws = [ \t\n\r]+;
|
|
ws { continue; }
|
|
|
|
// structural characters
|
|
"[" { last_token_type = token_type::begin_array; break; }
|
|
"]" { last_token_type = token_type::end_array; break; }
|
|
"{" { last_token_type = token_type::begin_object; break; }
|
|
"}" { last_token_type = token_type::end_object; break; }
|
|
"," { last_token_type = token_type::value_separator; break; }
|
|
":" { last_token_type = token_type::name_separator; break; }
|
|
|
|
// literal names
|
|
"null" { last_token_type = token_type::literal_null; break; }
|
|
"true" { last_token_type = token_type::literal_true; break; }
|
|
"false" { last_token_type = token_type::literal_false; break; }
|
|
|
|
// number
|
|
decimal_point = ".";
|
|
digit = [0-9];
|
|
digit_1_9 = [1-9];
|
|
e = "e" | "E";
|
|
minus = "-";
|
|
plus = "+";
|
|
zero = "0";
|
|
exp = e (minus | plus)? digit+;
|
|
frac = decimal_point digit+;
|
|
int = (zero | digit_1_9 digit*);
|
|
number = minus? int frac? exp?;
|
|
number { last_token_type = token_type::value_number; break; }
|
|
|
|
// string
|
|
quotation_mark = "\"";
|
|
escape = "\\";
|
|
unescaped = [^"\\\x00-\x1f];
|
|
single_escaped = "\"" | "\\" | "/" | "b" | "f" | "n" | "r" | "t";
|
|
unicode_escaped = "u" [0-9a-fA-F]{4};
|
|
escaped = escape (single_escaped | unicode_escaped);
|
|
char = unescaped | escaped;
|
|
string = quotation_mark char* quotation_mark;
|
|
string { last_token_type = token_type::value_string; break; }
|
|
|
|
// end of file
|
|
"\x00" { last_token_type = token_type::end_of_input; break; }
|
|
|
|
// anything else is an error
|
|
* { last_token_type = token_type::parse_error; break; }
|
|
*/
|
|
}
|
|
|
|
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 size_t 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 standand 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
|
|
indefinitly if i is always decreased. However, observe that the value
|
|
of i is strictly increasing with each iteration, as it is incremented
|
|
by 1 in the iteration expression and never decremented inside the loop
|
|
body. Hence, the loop condition will eventually be false which
|
|
contradicts the assumption that the loop condition is a tautology,
|
|
q.e.d.
|
|
|
|
@return string value of current token without opening and closing
|
|
quotes
|
|
@throw std::out_of_range if to_unicode fails
|
|
*/
|
|
string_t get_string() const
|
|
{
|
|
assert(m_cursor - m_start >= 2);
|
|
|
|
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')
|
|
{
|
|
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
|
|
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 floating point number
|
|
|
|
This function (and its overloads) serves to select the most approprate
|
|
standard floating point number parsing function based on the type
|
|
supplied via the first parameter. Set this to @a
|
|
static_cast<number_float_t*>(nullptr).
|
|
|
|
@param[in,out] endptr recieves a pointer to the first character after
|
|
the number
|
|
|
|
@return the floating point number
|
|
*/
|
|
long double str_to_float_t(long double* /* type */, char** endptr) const
|
|
{
|
|
return std::strtold(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr);
|
|
}
|
|
|
|
/*!
|
|
@brief parse floating point number
|
|
|
|
This function (and its overloads) serves to select the most approprate
|
|
standard floating point number parsing function based on the type
|
|
supplied via the first parameter. Set this to @a
|
|
static_cast<number_float_t*>(nullptr).
|
|
|
|
@param[in,out] endptr recieves a pointer to the first character after
|
|
the number
|
|
|
|
@return the floating point number
|
|
*/
|
|
double str_to_float_t(double* /* type */, char** endptr) const
|
|
{
|
|
return std::strtod(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr);
|
|
}
|
|
|
|
/*!
|
|
@brief parse floating point number
|
|
|
|
This function (and its overloads) serves to select the most approprate
|
|
standard floating point number parsing function based on the type
|
|
supplied via the first parameter. Set this to @a
|
|
static_cast<number_float_t*>(nullptr).
|
|
|
|
@param[in,out] endptr recieves a pointer to the first character after
|
|
the number
|
|
|
|
@return the floating point number
|
|
*/
|
|
float str_to_float_t(float* /* type */, char** endptr) const
|
|
{
|
|
return std::strtof(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr);
|
|
}
|
|
|
|
/*!
|
|
@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.
|
|
|
|
This function parses the integer component up to the radix point or
|
|
exponent while collecting information about the 'floating point
|
|
representation', which it stores in the result parameter. If there is
|
|
no radix point or exponent, and the number can fit into a @ref
|
|
number_integer_t or @ref number_unsigned_t then it sets the result
|
|
parameter accordingly.
|
|
|
|
If the number is a floating point number the number is then parsed
|
|
using @a std:strtod (or @a std:strtof or @a std::strtold).
|
|
|
|
@param[out] result @ref basic_json object to receive the number, or
|
|
NAN if the conversion read past the current token. The latter case
|
|
needs to be treated by the caller function.
|
|
*/
|
|
void get_number(basic_json& result) const
|
|
{
|
|
assert(m_start != nullptr);
|
|
|
|
const lexer::lexer_char_t* curptr = m_start;
|
|
|
|
// accumulate the integer conversion result (unsigned for now)
|
|
number_unsigned_t value = 0;
|
|
|
|
// maximum absolute value of the relevant integer type
|
|
number_unsigned_t max;
|
|
|
|
// temporarily store the type to avoid unecessary bitfield access
|
|
value_t type;
|
|
|
|
// look for sign
|
|
if (*curptr == '-')
|
|
{
|
|
type = value_t::number_integer;
|
|
max = static_cast<uint64_t>((std::numeric_limits<number_integer_t>::max)()) + 1;
|
|
curptr++;
|
|
}
|
|
else
|
|
{
|
|
type = value_t::number_unsigned;
|
|
max = static_cast<uint64_t>((std::numeric_limits<number_unsigned_t>::max)());
|
|
}
|
|
|
|
// count the significant figures
|
|
for (; curptr < m_cursor; curptr++)
|
|
{
|
|
// quickly skip tests if a digit
|
|
if (*curptr < '0' || *curptr > '9')
|
|
{
|
|
if (*curptr == '.')
|
|
{
|
|
// don't count '.' but change to float
|
|
type = value_t::number_float;
|
|
continue;
|
|
}
|
|
// assume exponent (if not then will fail parse): change to
|
|
// float, stop counting and record exponent details
|
|
type = value_t::number_float;
|
|
break;
|
|
}
|
|
|
|
// skip if definitely not an integer
|
|
if (type != value_t::number_float)
|
|
{
|
|
// multiply last value by ten and add the new digit
|
|
auto temp = value * 10 + *curptr - '0';
|
|
|
|
// test for overflow
|
|
if (temp < value || temp > max)
|
|
{
|
|
// overflow
|
|
type = value_t::number_float;
|
|
}
|
|
else
|
|
{
|
|
// no overflow - save it
|
|
value = temp;
|
|
}
|
|
}
|
|
}
|
|
|
|
// save the value (if not a float)
|
|
if (type == value_t::number_unsigned)
|
|
{
|
|
result.m_value.number_unsigned = value;
|
|
}
|
|
else if (type == value_t::number_integer)
|
|
{
|
|
result.m_value.number_integer = -static_cast<number_integer_t>(value);
|
|
}
|
|
else
|
|
{
|
|
// parse with strtod
|
|
result.m_value.number_float = str_to_float_t(static_cast<number_float_t*>(nullptr), NULL);
|
|
|
|
// replace infinity and NAN by null
|
|
if (not std::isfinite(result.m_value.number_float))
|
|
{
|
|
type = value_t::null;
|
|
result.m_value = basic_json::json_value();
|
|
}
|
|
}
|
|
|
|
// save the type
|
|
result.m_type = type;
|
|
}
|
|
|
|
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_number:
|
|
{
|
|
m_lexer.get_number(result);
|
|
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);
|
|
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));
|
|
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())
|
|
{
|
|
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())
|
|
{
|
|
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:
|
|
{
|
|
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')
|
|
{
|
|
throw std::domain_error("array index must not begin with '0'");
|
|
}
|
|
|
|
if (reference_token == "-")
|
|
{
|
|
// explicityly 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:
|
|
{
|
|
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
|
|
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')
|
|
{
|
|
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:
|
|
{
|
|
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
|
|
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')
|
|
{
|
|
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:
|
|
{
|
|
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
|
|
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')
|
|
{
|
|
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:
|
|
{
|
|
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] != '/')
|
|
{
|
|
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'))
|
|
{
|
|
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())
|
|
{
|
|
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())
|
|
{
|
|
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:
|
|
/// 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 primitve 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 funcion, 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
|
|
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
|
|
{
|
|
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
|
|
throw std::invalid_argument("JSON patch must be an array of objects");
|
|
}
|
|
|
|
// iterate and apply th eoperations
|
|
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())
|
|
{
|
|
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())
|
|
{
|
|
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())
|
|
{
|
|
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;
|
|
try
|
|
{
|
|
// check if "value" matches the one at "path"
|
|
// the "path" location must exist - use at()
|
|
success = (result.at(ptr) == get_value("test", "value", false));
|
|
}
|
|
catch (std::out_of_range&)
|
|
{
|
|
// ignore out of range errors: success remains false
|
|
}
|
|
|
|
// throw an exception if test fails
|
|
if (not success)
|
|
{
|
|
throw std::domain_error("unsuccessful: " + val.dump());
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
case patch_operations::invalid:
|
|
{
|
|
// op must be "add", "remove", "replace", "move", "copy", or
|
|
// "test"
|
|
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 copare from
|
|
@param[in] target JSON value to copare 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<>;
|
|
}
|
|
|
|
|
|
///////////////////////
|
|
// 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());
|
|
}
|
|
};
|
|
}
|
|
|
|
/*!
|
|
@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
|
|
|
|
#endif
|