/src/jsonnet/third_party/json/json.hpp

Source (jump to first uncovered line)
/*
    __ _____ _____ _____
 __|  |   __|     |   | |  JSON for Modern C++
|  |  |__   |  |  | | | |  version 3.6.1
|_____|_____|_____|_|___|  https://github.com/nlohmann/json

Licensed under the MIT License <http://opensource.org/licenses/MIT>.
SPDX-License-Identifier: MIT
Copyright (c) 2013-2019 Niels Lohmann <http://nlohmann.me>.

Permission is hereby  granted, free of charge, to any  person obtaining a copy
of this software and associated  documentation files (the "Software"), to deal
in the Software  without restriction, including without  limitation the rights
to  use, copy,  modify, merge,  publish, distribute,  sublicense, and/or  sell
copies  of  the Software,  and  to  permit persons  to  whom  the Software  is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE  IS PROVIDED "AS  IS", WITHOUT WARRANTY  OF ANY KIND,  EXPRESS OR
IMPLIED,  INCLUDING BUT  NOT  LIMITED TO  THE  WARRANTIES OF  MERCHANTABILITY,
FITNESS FOR  A PARTICULAR PURPOSE AND  NONINFRINGEMENT. IN NO EVENT  SHALL THE
AUTHORS  OR COPYRIGHT  HOLDERS  BE  LIABLE FOR  ANY  CLAIM,  DAMAGES OR  OTHER
LIABILITY, WHETHER IN AN ACTION OF  CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE  OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

#ifndef INCLUDE_NLOHMANN_JSON_HPP_
#define INCLUDE_NLOHMANN_JSON_HPP_

#define NLOHMANN_JSON_VERSION_MAJOR 3
#define NLOHMANN_JSON_VERSION_MINOR 6
#define NLOHMANN_JSON_VERSION_PATCH 1

#include <algorithm> // all_of, find, for_each
#include <cassert> // assert
#include <ciso646> // and, not, or
#include <cstddef> // nullptr_t, ptrdiff_t, size_t
#include <functional> // hash, less
#include <initializer_list> // initializer_list
#include <iosfwd> // istream, ostream
#include <iterator> // random_access_iterator_tag
#include <memory> // unique_ptr
#include <numeric> // accumulate
#include <string> // string, stoi, to_string
#include <utility> // declval, forward, move, pair, swap
#include <vector> // vector

// #include <nlohmann/adl_serializer.hpp>


#include <utility>

// #include <nlohmann/detail/conversions/from_json.hpp>


#include <algorithm> // transform
#include <array> // array
#include <ciso646> // and, not
#include <forward_list> // forward_list
#include <iterator> // inserter, front_inserter, end
#include <map> // map
#include <string> // string
#include <tuple> // tuple, make_tuple
#include <type_traits> // is_arithmetic, is_same, is_enum, underlying_type, is_convertible
#include <unordered_map> // unordered_map
#include <utility> // pair, declval
#include <valarray> // valarray

// #include <nlohmann/detail/exceptions.hpp>


#include <exception> // exception
#include <stdexcept> // runtime_error
#include <string> // to_string

// #include <nlohmann/detail/input/position_t.hpp>


#include <cstddef> // size_t

namespace nlohmann
{
namespace detail
{
/// struct to capture the start position of the current token
struct position_t
{
    /// the total number of characters read
    std::size_t chars_read_total = 0;
    /// the number of characters read in the current line
    std::size_t chars_read_current_line = 0;
    /// the number of lines read
    std::size_t lines_read = 0;

    /// conversion to size_t to preserve SAX interface
    constexpr operator size_t() const
    {
        return chars_read_total;
    }
};

} // namespace detail
} // namespace nlohmann


namespace nlohmann
{
namespace detail
{
////////////////
// exceptions //
////////////////

/*!
@brief general exception of the @ref basic_json class

This class is an extension of `std::exception` objects with a member @a id for
exception ids. It is used as the base class for all exceptions thrown by the
@ref basic_json class. This class can hence be used as "wildcard" to catch
exceptions.

Subclasses:
- @ref parse_error for exceptions indicating a parse error
- @ref invalid_iterator for exceptions indicating errors with iterators
- @ref type_error for exceptions indicating executing a member function with
                  a wrong type
- @ref out_of_range for exceptions indicating access out of the defined range
- @ref other_error for exceptions indicating other library errors

@internal
@note To have nothrow-copy-constructible exceptions, we internally use
      `std::runtime_error` which can cope with arbitrary-length error messages.
      Intermediate strings are built with static functions and then passed to
      the actual constructor.
@endinternal

@liveexample{The following code shows how arbitrary library exceptions can be
caught.,exception}

@since version 3.0.0
*/
class exception : public std::exception
{
  public:
    /// returns the explanatory string
    const char* what() const noexcept override
    {
        return m.what();
    }

    /// the id of the exception
    const int id;

  protected:
    exception(int id_, const char* what_arg) : id(id_), m(what_arg) {}

    static std::string name(const std::string& ename, int id_)
    {
        return "[json.exception." + ename + "." + std::to_string(id_) + "] ";
    }

  private:
    /// an exception object as storage for error messages
    std::runtime_error m;
};

/*!
@brief exception indicating a parse error

This exception is thrown by the library when a parse error occurs. Parse errors
can occur during the deserialization of JSON text, CBOR, MessagePack, as well
as when using JSON Patch.

Member @a byte holds the byte index of the last read character in the input
file.

Exceptions have ids 1xx.

name / id                      | example message | description
------------------------------ | --------------- | -------------------------
json.exception.parse_error.101 | parse error at 2: unexpected end of input; expected string literal | This error indicates a syntax error while deserializing a JSON text. The error message describes that an unexpected token (character) was encountered, and the member @a byte indicates the error position.
json.exception.parse_error.102 | parse error at 14: missing or wrong low surrogate | JSON uses the `\uxxxx` format to describe Unicode characters. Code points above above 0xFFFF are split into two `\uxxxx` entries ("surrogate pairs"). This error indicates that the surrogate pair is incomplete or contains an invalid code point.
json.exception.parse_error.103 | parse error: code points above 0x10FFFF are invalid | Unicode supports code points up to 0x10FFFF. Code points above 0x10FFFF are invalid.
json.exception.parse_error.104 | parse error: JSON patch must be an array of objects | [RFC 6902](https://tools.ietf.org/html/rfc6902) requires a JSON Patch document to be a JSON document that represents an array of objects.
json.exception.parse_error.105 | parse error: operation must have string member 'op' | An operation of a JSON Patch document must contain exactly one "op" member, whose value indicates the operation to perform. Its value must be one of "add", "remove", "replace", "move", "copy", or "test"; other values are errors.
json.exception.parse_error.106 | parse error: array index '01' must not begin with '0' | An array index in a JSON Pointer ([RFC 6901](https://tools.ietf.org/html/rfc6901)) may be `0` or any number without a leading `0`.
json.exception.parse_error.107 | parse error: JSON pointer must be empty or begin with '/' - was: 'foo' | A JSON Pointer must be a Unicode string containing a sequence of zero or more reference tokens, each prefixed by a `/` character.
json.exception.parse_error.108 | parse error: escape character '~' must be followed with '0' or '1' | In a JSON Pointer, only `~0` and `~1` are valid escape sequences.
json.exception.parse_error.109 | parse error: array index 'one' is not a number | A JSON Pointer array index must be a number.
json.exception.parse_error.110 | parse error at 1: cannot read 2 bytes from vector | When parsing CBOR or MessagePack, the byte vector ends before the complete value has been read.
json.exception.parse_error.112 | parse error at 1: error reading CBOR; last byte: 0xF8 | Not all types of CBOR or MessagePack are supported. This exception occurs if an unsupported byte was read.
json.exception.parse_error.113 | parse error at 2: expected a CBOR string; last byte: 0x98 | While parsing a map key, a value that is not a string has been read.
json.exception.parse_error.114 | parse error: Unsupported BSON record type 0x0F | The parsing of the corresponding BSON record type is not implemented (yet).

@note For an input with n bytes, 1 is the index of the first character and n+1
      is the index of the terminating null byte or the end of file. This also
      holds true when reading a byte vector (CBOR or MessagePack).

@liveexample{The following code shows how a `parse_error` exception can be
caught.,parse_error}

@sa - @ref exception for the base class of the library exceptions
@sa - @ref invalid_iterator for exceptions indicating errors with iterators
@sa - @ref type_error for exceptions indicating executing a member function with
                    a wrong type
@sa - @ref out_of_range for exceptions indicating access out of the defined range
@sa - @ref other_error for exceptions indicating other library errors

@since version 3.0.0
*/
class parse_error : public exception
{
  public:
    /*!
    @brief create a parse error exception
    @param[in] id_       the id of the exception
    @param[in] pos       the position where the error occurred (or with
                         chars_read_total=0 if the position cannot be
                         determined)
    @param[in] what_arg  the explanatory string
    @return parse_error object
    */
    static parse_error create(int id_, const position_t& pos, const std::string& what_arg)
    {
        std::string w = exception::name("parse_error", id_) + "parse error" +
                        position_string(pos) + ": " + what_arg;
        return parse_error(id_, pos.chars_read_total, w.c_str());
    }

    static parse_error create(int id_, std::size_t byte_, const std::string& what_arg)
    {
        std::string w = exception::name("parse_error", id_) + "parse error" +
                        (byte_ != 0 ? (" at byte " + std::to_string(byte_)) : "") +
                        ": " + what_arg;
        return parse_error(id_, byte_, w.c_str());
    }

    /*!
    @brief byte index of the parse error

    The byte index of the last read character in the input file.

    @note For an input with n bytes, 1 is the index of the first character and
          n+1 is the index of the terminating null byte or the end of file.
          This also holds true when reading a byte vector (CBOR or MessagePack).
    */
    const std::size_t byte;

  private:
    parse_error(int id_, std::size_t byte_, const char* what_arg)
        : exception(id_, what_arg), byte(byte_) {}

    static std::string position_string(const position_t& pos)
    {
        return " at line " + std::to_string(pos.lines_read + 1) +
               ", column " + std::to_string(pos.chars_read_current_line);
    }
};

/*!
@brief exception indicating errors with iterators

This exception is thrown if iterators passed to a library function do not match
the expected semantics.

Exceptions have ids 2xx.

name / id                           | example message | description
----------------------------------- | --------------- | -------------------------
json.exception.invalid_iterator.201 | iterators are not compatible | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid.
json.exception.invalid_iterator.202 | iterator does not fit current value | In an erase or insert function, the passed iterator @a pos does not belong to the JSON value for which the function was called. It hence does not define a valid position for the deletion/insertion.
json.exception.invalid_iterator.203 | iterators do not fit current value | Either iterator passed to function @ref erase(IteratorType first, IteratorType last) does not belong to the JSON value from which values shall be erased. It hence does not define a valid range to delete values from.
json.exception.invalid_iterator.204 | iterators out of range | When an iterator range for a primitive type (number, boolean, or string) is passed to a constructor or an erase function, this range has to be exactly (@ref begin(), @ref end()), because this is the only way the single stored value is expressed. All other ranges are invalid.
json.exception.invalid_iterator.205 | iterator out of range | When an iterator for a primitive type (number, boolean, or string) is passed to an erase function, the iterator has to be the @ref begin() iterator, because it is the only way to address the stored value. All other iterators are invalid.
json.exception.invalid_iterator.206 | cannot construct with iterators from null | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) belong to a JSON null value and hence to not define a valid range.
json.exception.invalid_iterator.207 | cannot use key() for non-object iterators | The key() member function can only be used on iterators belonging to a JSON object, because other types do not have a concept of a key.
json.exception.invalid_iterator.208 | cannot use operator[] for object iterators | The operator[] to specify a concrete offset cannot be used on iterators belonging to a JSON object, because JSON objects are unordered.
json.exception.invalid_iterator.209 | cannot use offsets with object iterators | The offset operators (+, -, +=, -=) cannot be used on iterators belonging to a JSON object, because JSON objects are unordered.
json.exception.invalid_iterator.210 | iterators do not fit | The iterator range passed to the insert function are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid.
json.exception.invalid_iterator.211 | passed iterators may not belong to container | The iterator range passed to the insert function must not be a subrange of the container to insert to.
json.exception.invalid_iterator.212 | cannot compare iterators of different containers | When two iterators are compared, they must belong to the same container.
json.exception.invalid_iterator.213 | cannot compare order of object iterators | The order of object iterators cannot be compared, because JSON objects are unordered.
json.exception.invalid_iterator.214 | cannot get value | Cannot get value for iterator: Either the iterator belongs to a null value or it is an iterator to a primitive type (number, boolean, or string), but the iterator is different to @ref begin().

@liveexample{The following code shows how an `invalid_iterator` exception can be
caught.,invalid_iterator}

@sa - @ref exception for the base class of the library exceptions
@sa - @ref parse_error for exceptions indicating a parse error
@sa - @ref type_error for exceptions indicating executing a member function with
                    a wrong type
@sa - @ref out_of_range for exceptions indicating access out of the defined range
@sa - @ref other_error for exceptions indicating other library errors

@since version 3.0.0
*/
class invalid_iterator : public exception
{
  public:
    static invalid_iterator create(int id_, const std::string& what_arg)
    {
        std::string w = exception::name("invalid_iterator", id_) + what_arg;
        return invalid_iterator(id_, w.c_str());
    }

  private:
    invalid_iterator(int id_, const char* what_arg)
        : exception(id_, what_arg) {}
};

/*!
@brief exception indicating executing a member function with a wrong type

This exception is thrown in case of a type error; that is, a library function is
executed on a JSON value whose type does not match the expected semantics.

Exceptions have ids 3xx.

name / id                     | example message | description
----------------------------- | --------------- | -------------------------
json.exception.type_error.301 | cannot create object from initializer list | To create an object from an initializer list, the initializer list must consist only of a list of pairs whose first element is a string. When this constraint is violated, an array is created instead.
json.exception.type_error.302 | type must be object, but is array | During implicit or explicit value conversion, the JSON type must be compatible to the target type. For instance, a JSON string can only be converted into string types, but not into numbers or boolean types.
json.exception.type_error.303 | incompatible ReferenceType for get_ref, actual type is object | To retrieve a reference to a value stored in a @ref basic_json object with @ref get_ref, the type of the reference must match the value type. For instance, for a JSON array, the @a ReferenceType must be @ref array_t &.
json.exception.type_error.304 | cannot use at() with string | The @ref at() member functions can only be executed for certain JSON types.
json.exception.type_error.305 | cannot use operator[] with string | The @ref operator[] member functions can only be executed for certain JSON types.
json.exception.type_error.306 | cannot use value() with string | The @ref value() member functions can only be executed for certain JSON types.
json.exception.type_error.307 | cannot use erase() with string | The @ref erase() member functions can only be executed for certain JSON types.
json.exception.type_error.308 | cannot use push_back() with string | The @ref push_back() and @ref operator+= member functions can only be executed for certain JSON types.
json.exception.type_error.309 | cannot use insert() with | The @ref insert() member functions can only be executed for certain JSON types.
json.exception.type_error.310 | cannot use swap() with number | The @ref swap() member functions can only be executed for certain JSON types.
json.exception.type_error.311 | cannot use emplace_back() with string | The @ref emplace_back() member function can only be executed for certain JSON types.
json.exception.type_error.312 | cannot use update() with string | The @ref update() member functions can only be executed for certain JSON types.
json.exception.type_error.313 | invalid value to unflatten | The @ref unflatten function converts an object whose keys are JSON Pointers back into an arbitrary nested JSON value. The JSON Pointers must not overlap, because then the resulting value would not be well defined.
json.exception.type_error.314 | only objects can be unflattened | The @ref unflatten function only works for an object whose keys are JSON Pointers.
json.exception.type_error.315 | values in object must be primitive | The @ref unflatten function only works for an object whose keys are JSON Pointers and whose values are primitive.
json.exception.type_error.316 | invalid UTF-8 byte at index 10: 0x7E | The @ref dump function only works with UTF-8 encoded strings; that is, if you assign a `std::string` to a JSON value, make sure it is UTF-8 encoded. |
json.exception.type_error.317 | JSON value cannot be serialized to requested format | The dynamic type of the object cannot be represented in the requested serialization format (e.g. a raw `true` or `null` JSON object cannot be serialized to BSON) |

@liveexample{The following code shows how a `type_error` exception can be
caught.,type_error}

@sa - @ref exception for the base class of the library exceptions
@sa - @ref parse_error for exceptions indicating a parse error
@sa - @ref invalid_iterator for exceptions indicating errors with iterators
@sa - @ref out_of_range for exceptions indicating access out of the defined range
@sa - @ref other_error for exceptions indicating other library errors

@since version 3.0.0
*/
class type_error : public exception
{
  public:
    static type_error create(int id_, const std::string& what_arg)
    {
        std::string w = exception::name("type_error", id_) + what_arg;
        return type_error(id_, w.c_str());
    }

  private:
    type_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
};

/*!
@brief exception indicating access out of the defined range

This exception is thrown in case a library function is called on an input
parameter that exceeds the expected range, for instance in case of array
indices or nonexisting object keys.

Exceptions have ids 4xx.

name / id                       | example message | description
------------------------------- | --------------- | -------------------------
json.exception.out_of_range.401 | array index 3 is out of range | The provided array index @a i is larger than @a size-1.
json.exception.out_of_range.402 | array index '-' (3) is out of range | The special array index `-` in a JSON Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it.
json.exception.out_of_range.403 | key 'foo' not found | The provided key was not found in the JSON object.
json.exception.out_of_range.404 | unresolved reference token 'foo' | A reference token in a JSON Pointer could not be resolved.
json.exception.out_of_range.405 | JSON pointer has no parent | The JSON Patch operations 'remove' and 'add' can not be applied to the root element of the JSON value.
json.exception.out_of_range.406 | number overflow parsing '10E1000' | A parsed number could not be stored as without changing it to NaN or INF.
json.exception.out_of_range.407 | number overflow serializing '9223372036854775808' | UBJSON and BSON only support integer numbers up to 9223372036854775807. |
json.exception.out_of_range.408 | excessive array size: 8658170730974374167 | The size (following `#`) of an UBJSON array or object exceeds the maximal capacity. |
json.exception.out_of_range.409 | BSON key cannot contain code point U+0000 (at byte 2) | Key identifiers to be serialized to BSON cannot contain code point U+0000, since the key is stored as zero-terminated c-string |

@liveexample{The following code shows how an `out_of_range` exception can be
caught.,out_of_range}

@sa - @ref exception for the base class of the library exceptions
@sa - @ref parse_error for exceptions indicating a parse error
@sa - @ref invalid_iterator for exceptions indicating errors with iterators
@sa - @ref type_error for exceptions indicating executing a member function with
                    a wrong type
@sa - @ref other_error for exceptions indicating other library errors

@since version 3.0.0
*/
class out_of_range : public exception
{
  public:
    static out_of_range create(int id_, const std::string& what_arg)
    {
        std::string w = exception::name("out_of_range", id_) + what_arg;
        return out_of_range(id_, w.c_str());
    }

  private:
    out_of_range(int id_, const char* what_arg) : exception(id_, what_arg) {}
};

/*!
@brief exception indicating other library errors

This exception is thrown in case of errors that cannot be classified with the
other exception types.

Exceptions have ids 5xx.

name / id                      | example message | description
------------------------------ | --------------- | -------------------------
json.exception.other_error.501 | unsuccessful: {"op":"test","path":"/baz", "value":"bar"} | A JSON Patch operation 'test' failed. The unsuccessful operation is also printed.

@sa - @ref exception for the base class of the library exceptions
@sa - @ref parse_error for exceptions indicating a parse error
@sa - @ref invalid_iterator for exceptions indicating errors with iterators
@sa - @ref type_error for exceptions indicating executing a member function with
                    a wrong type
@sa - @ref out_of_range for exceptions indicating access out of the defined range

@liveexample{The following code shows how an `other_error` exception can be
caught.,other_error}

@since version 3.0.0
*/
class other_error : public exception
{
  public:
    static other_error create(int id_, const std::string& what_arg)
    {
        std::string w = exception::name("other_error", id_) + what_arg;
        return other_error(id_, w.c_str());
    }

  private:
    other_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
};
}  // namespace detail
}  // namespace nlohmann

// #include <nlohmann/detail/macro_scope.hpp>


#include <utility> // pair

// This file contains all internal macro definitions
// You MUST include macro_unscope.hpp at the end of json.hpp to undef all of them

// exclude unsupported compilers
#if !defined(JSON_SKIP_UNSUPPORTED_COMPILER_CHECK)
    #if defined(__clang__)
        #if (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__) < 30400
            #error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers"
        #endif
    #elif defined(__GNUC__) && !(defined(__ICC) || defined(__INTEL_COMPILER))
        #if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) < 40800
            #error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers"
        #endif
    #endif
#endif

// disable float-equal warnings on GCC/clang
#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
    #pragma GCC diagnostic push
    #pragma GCC diagnostic ignored "-Wfloat-equal"
#endif

// disable documentation warnings on clang
#if defined(__clang__)
    #pragma GCC diagnostic push
    #pragma GCC diagnostic ignored "-Wdocumentation"
#endif

// allow for portable deprecation warnings
#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
    #define JSON_DEPRECATED __attribute__((deprecated))
#elif defined(_MSC_VER)
    #define JSON_DEPRECATED __declspec(deprecated)
#else
    #define JSON_DEPRECATED
#endif

// allow for portable nodiscard warnings
#if defined(__has_cpp_attribute)
    #if __has_cpp_attribute(nodiscard)
        #define JSON_NODISCARD [[nodiscard]]
    #elif __has_cpp_attribute(gnu::warn_unused_result)
        #define JSON_NODISCARD [[gnu::warn_unused_result]]
    #else
        #define JSON_NODISCARD
    #endif
#else
    #define JSON_NODISCARD
#endif

// allow to disable exceptions
#if (defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND)) && !defined(JSON_NOEXCEPTION)
    #define JSON_THROW(exception) throw exception
    #define JSON_TRY try
    #define JSON_CATCH(exception) catch(exception)
    #define JSON_INTERNAL_CATCH(exception) catch(exception)
#else
    #include <cstdlib>
    #define JSON_THROW(exception) std::abort()
    #define JSON_TRY if(true)
    #define JSON_CATCH(exception) if(false)
    #define JSON_INTERNAL_CATCH(exception) if(false)
#endif

// override exception macros
#if defined(JSON_THROW_USER)
    #undef JSON_THROW
    #define JSON_THROW JSON_THROW_USER
#endif
#if defined(JSON_TRY_USER)
    #undef JSON_TRY
    #define JSON_TRY JSON_TRY_USER
#endif
#if defined(JSON_CATCH_USER)
    #undef JSON_CATCH
    #define JSON_CATCH JSON_CATCH_USER
    #undef JSON_INTERNAL_CATCH
    #define JSON_INTERNAL_CATCH JSON_CATCH_USER
#endif
#if defined(JSON_INTERNAL_CATCH_USER)
    #undef JSON_INTERNAL_CATCH
    #define JSON_INTERNAL_CATCH JSON_INTERNAL_CATCH_USER
#endif

// manual branch prediction
#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
    #define JSON_LIKELY(x)      __builtin_expect(x, 1)
    #define JSON_UNLIKELY(x)    __builtin_expect(x, 0)
#else
    #define JSON_LIKELY(x)      x
    #define JSON_UNLIKELY(x)    x
#endif

// C++ language standard detection
#if (defined(__cplusplus) && __cplusplus >= 201703L) || (defined(_HAS_CXX17) && _HAS_CXX17 == 1) // fix for issue #464
    #define JSON_HAS_CPP_17
    #define JSON_HAS_CPP_14
#elif (defined(__cplusplus) && __cplusplus >= 201402L) || (defined(_HAS_CXX14) && _HAS_CXX14 == 1)
    #define JSON_HAS_CPP_14
#endif

/*!
@brief macro to briefly define a mapping between an enum and JSON
@def NLOHMANN_JSON_SERIALIZE_ENUM
@since version 3.4.0
*/
#define NLOHMANN_JSON_SERIALIZE_ENUM(ENUM_TYPE, ...)                                           \
    template<typename BasicJsonType>                                                           \
    inline void to_json(BasicJsonType& j, const ENUM_TYPE& e)                                  \
    {                                                                                          \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");         \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                    \
        auto it = std::find_if(std::begin(m), std::end(m),                                     \
                               [e](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
        {                                                                                      \
            return ej_pair.first == e;                                                         \
        });                                                                                    \
        j = ((it != std::end(m)) ? it : std::begin(m))->second;                                \
    }                                                                                          \
    template<typename BasicJsonType>                                                           \
    inline void from_json(const BasicJsonType& j, ENUM_TYPE& e)                                \
    {                                                                                          \
        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");         \
        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                    \
        auto it = std::find_if(std::begin(m), std::end(m),                                     \
                               [j](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
        {                                                                                      \
            return ej_pair.second == j;                                                        \
        });                                                                                    \
        e = ((it != std::end(m)) ? it : std::begin(m))->first;                                 \
    }

// Ugly macros to avoid uglier copy-paste when specializing basic_json. They
// may be removed in the future once the class is split.

#define NLOHMANN_BASIC_JSON_TPL_DECLARATION                                \
    template<template<typename, typename, typename...> class ObjectType,   \
             template<typename, typename...> class ArrayType,              \
             class StringType, class BooleanType, class NumberIntegerType, \
             class NumberUnsignedType, class NumberFloatType,              \
             template<typename> class AllocatorType,                       \
             template<typename, typename = void> class JSONSerializer>

#define NLOHMANN_BASIC_JSON_TPL                                            \
    basic_json<ObjectType, ArrayType, StringType, BooleanType,             \
    NumberIntegerType, NumberUnsignedType, NumberFloatType,                \
    AllocatorType, JSONSerializer>

// #include <nlohmann/detail/meta/cpp_future.hpp>


#include <ciso646> // not
#include <cstddef> // size_t
#include <type_traits> // conditional, enable_if, false_type, integral_constant, is_constructible, is_integral, is_same, remove_cv, remove_reference, true_type

namespace nlohmann
{
namespace detail
{
// alias templates to reduce boilerplate
template<bool B, typename T = void>
using enable_if_t = typename std::enable_if<B, T>::type;

template<typename T>
using uncvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type;

// implementation of C++14 index_sequence and affiliates
// source: https://stackoverflow.com/a/32223343
template<std::size_t... Ints>
struct index_sequence
{
    using type = index_sequence;
    using value_type = std::size_t;
    static constexpr std::size_t size() noexcept
    {
        return sizeof...(Ints);
    }
};

template<class Sequence1, class Sequence2>
struct merge_and_renumber;

template<std::size_t... I1, std::size_t... I2>
struct merge_and_renumber<index_sequence<I1...>, index_sequence<I2...>>
        : index_sequence < I1..., (sizeof...(I1) + I2)... > {};

template<std::size_t N>
struct make_index_sequence
    : merge_and_renumber < typename make_index_sequence < N / 2 >::type,
      typename make_index_sequence < N - N / 2 >::type > {};

template<> struct make_index_sequence<0> : index_sequence<> {};
template<> struct make_index_sequence<1> : index_sequence<0> {};

template<typename... Ts>
using index_sequence_for = make_index_sequence<sizeof...(Ts)>;

// dispatch utility (taken from ranges-v3)
template<unsigned N> struct priority_tag : priority_tag < N - 1 > {};
template<> struct priority_tag<0> {};

// taken from ranges-v3
template<typename T>
struct static_const
{
    static constexpr T value{};
};

template<typename T>
constexpr T static_const<T>::value;
}  // namespace detail
}  // namespace nlohmann

// #include <nlohmann/detail/meta/type_traits.hpp>


#include <ciso646> // not
#include <limits> // numeric_limits
#include <type_traits> // false_type, is_constructible, is_integral, is_same, true_type
#include <utility> // declval

// #include <nlohmann/detail/iterators/iterator_traits.hpp>


#include <iterator> // random_access_iterator_tag

// #include <nlohmann/detail/meta/void_t.hpp>


namespace nlohmann
{
namespace detail
{
template <typename ...Ts> struct make_void
{
    using type = void;
};
template <typename ...Ts> using void_t = typename make_void<Ts...>::type;
} // namespace detail
}  // namespace nlohmann

// #include <nlohmann/detail/meta/cpp_future.hpp>


namespace nlohmann
{
namespace detail
{
template <typename It, typename = void>
struct iterator_types {};

template <typename It>
struct iterator_types <
    It,
    void_t<typename It::difference_type, typename It::value_type, typename It::pointer,
    typename It::reference, typename It::iterator_category >>
{
    using difference_type = typename It::difference_type;
    using value_type = typename It::value_type;
    using pointer = typename It::pointer;
    using reference = typename It::reference;
    using iterator_category = typename It::iterator_category;
};

// This is required as some compilers implement std::iterator_traits in a way that
// doesn't work with SFINAE. See https://github.com/nlohmann/json/issues/1341.
template <typename T, typename = void>
struct iterator_traits
{
};

template <typename T>
struct iterator_traits < T, enable_if_t < !std::is_pointer<T>::value >>
            : iterator_types<T>
{
};

template <typename T>
struct iterator_traits<T*, enable_if_t<std::is_object<T>::value>>
{
    using iterator_category = std::random_access_iterator_tag;
    using value_type = T;
    using difference_type = ptrdiff_t;
    using pointer = T*;
    using reference = T&;
};
} // namespace detail
} // namespace nlohmann

// #include <nlohmann/detail/macro_scope.hpp>

// #include <nlohmann/detail/meta/cpp_future.hpp>

// #include <nlohmann/detail/meta/detected.hpp>


#include <type_traits>

// #include <nlohmann/detail/meta/void_t.hpp>


// http://en.cppreference.com/w/cpp/experimental/is_detected
namespace nlohmann
{
namespace detail
{
struct nonesuch
{
    nonesuch() = delete;
    ~nonesuch() = delete;
    nonesuch(nonesuch const&) = delete;
    nonesuch(nonesuch const&&) = delete;
    void operator=(nonesuch const&) = delete;
    void operator=(nonesuch&&) = delete;
};

template <class Default,
          class AlwaysVoid,
          template <class...> class Op,
          class... Args>
struct detector
{
    using value_t = std::false_type;
    using type = Default;
};

template <class Default, template <class...> class Op, class... Args>
struct detector<Default, void_t<Op<Args...>>, Op, Args...>
{
    using value_t = std::true_type;
    using type = Op<Args...>;
};

template <template <class...> class Op, class... Args>
using is_detected = typename detector<nonesuch, void, Op, Args...>::value_t;

template <template <class...> class Op, class... Args>
using detected_t = typename detector<nonesuch, void, Op, Args...>::type;

template <class Default, template <class...> class Op, class... Args>
using detected_or = detector<Default, void, Op, Args...>;

template <class Default, template <class...> class Op, class... Args>
using detected_or_t = typename detected_or<Default, Op, Args...>::type;

template <class Expected, template <class...> class Op, class... Args>
using is_detected_exact = std::is_same<Expected, detected_t<Op, Args...>>;

template <class To, template <class...> class Op, class... Args>
using is_detected_convertible =
    std::is_convertible<detected_t<Op, Args...>, To>;
}  // namespace detail
}  // namespace nlohmann

// #include <nlohmann/json_fwd.hpp>
#ifndef INCLUDE_NLOHMANN_JSON_FWD_HPP_
#define INCLUDE_NLOHMANN_JSON_FWD_HPP_

#include <cstdint> // int64_t, uint64_t
#include <map> // map
#include <memory> // allocator
#include <string> // string
#include <vector> // vector

/*!
@brief namespace for Niels Lohmann
@see https://github.com/nlohmann
@since version 1.0.0
*/
namespace nlohmann
{
/*!
@brief default JSONSerializer template argument

This serializer ignores the template arguments and uses ADL
([argument-dependent lookup](https://en.cppreference.com/w/cpp/language/adl))
for serialization.
*/
template<typename T = void, typename SFINAE = void>
struct adl_serializer;

template<template<typename U, typename V, typename... Args> class ObjectType =
         std::map,
         template<typename U, typename... Args> class ArrayType = std::vector,
         class StringType = std::string, class BooleanType = bool,
         class NumberIntegerType = std::int64_t,
         class NumberUnsignedType = std::uint64_t,
         class NumberFloatType = double,
         template<typename U> class AllocatorType = std::allocator,
         template<typename T, typename SFINAE = void> class JSONSerializer =
         adl_serializer>
class basic_json;

/*!
@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
*/
template<typename BasicJsonType>
class json_pointer;

/*!
@brief default JSON class

This type is the default specialization of the @ref basic_json class which
uses the standard template types.

@since version 1.0.0
*/
using json = basic_json<>;
}  // namespace nlohmann

#endif  // INCLUDE_NLOHMANN_JSON_FWD_HPP_


namespace nlohmann
{
/*!
@brief detail namespace with internal helper functions

This namespace collects functions that should not be exposed,
implementations of some @ref basic_json methods, and meta-programming helpers.

@since version 2.1.0
*/
namespace detail
{
/////////////
// helpers //
/////////////

// Note to maintainers:
//
// Every trait in this file expects a non CV-qualified type.
// The only exceptions are in the 'aliases for detected' section
// (i.e. those of the form: decltype(T::member_function(std::declval<T>())))
//
// In this case, T has to be properly CV-qualified to constraint the function arguments
// (e.g. to_json(BasicJsonType&, const T&))

template<typename> struct is_basic_json : std::false_type {};

NLOHMANN_BASIC_JSON_TPL_DECLARATION
struct is_basic_json<NLOHMANN_BASIC_JSON_TPL> : std::true_type {};

//////////////////////////
// aliases for detected //
//////////////////////////

template <typename T>
using mapped_type_t = typename T::mapped_type;

template <typename T>
using key_type_t = typename T::key_type;

template <typename T>
using value_type_t = typename T::value_type;

template <typename T>
using difference_type_t = typename T::difference_type;

template <typename T>
using pointer_t = typename T::pointer;

template <typename T>
using reference_t = typename T::reference;

template <typename T>
using iterator_category_t = typename T::iterator_category;

template <typename T>
using iterator_t = typename T::iterator;

template <typename T, typename... Args>
using to_json_function = decltype(T::to_json(std::declval<Args>()...));

template <typename T, typename... Args>
using from_json_function = decltype(T::from_json(std::declval<Args>()...));

template <typename T, typename U>
using get_template_function = decltype(std::declval<T>().template get<U>());

// trait checking if JSONSerializer<T>::from_json(json const&, udt&) exists
template <typename BasicJsonType, typename T, typename = void>
struct has_from_json : std::false_type {};

template <typename BasicJsonType, typename T>
struct has_from_json<BasicJsonType, T,
           enable_if_t<not is_basic_json<T>::value>>
{
    using serializer = typename BasicJsonType::template json_serializer<T, void>;

    static constexpr bool value =
        is_detected_exact<void, from_json_function, serializer,
        const BasicJsonType&, T&>::value;
};

// This trait checks if JSONSerializer<T>::from_json(json const&) exists
// this overload is used for non-default-constructible user-defined-types
template <typename BasicJsonType, typename T, typename = void>
struct has_non_default_from_json : std::false_type {};

template<typename BasicJsonType, typename T>
struct has_non_default_from_json<BasicJsonType, T, enable_if_t<not is_basic_json<T>::value>>
{
    using serializer = typename BasicJsonType::template json_serializer<T, void>;

    static constexpr bool value =
        is_detected_exact<T, from_json_function, serializer,
        const BasicJsonType&>::value;
};

// This trait checks if BasicJsonType::json_serializer<T>::to_json exists
// Do not evaluate the trait when T is a basic_json type, to avoid template instantiation infinite recursion.
template <typename BasicJsonType, typename T, typename = void>
struct has_to_json : std::false_type {};

template <typename BasicJsonType, typename T>
struct has_to_json<BasicJsonType, T, enable_if_t<not is_basic_json<T>::value>>
{
    using serializer = typename BasicJsonType::template json_serializer<T, void>;

    static constexpr bool value =
        is_detected_exact<void, to_json_function, serializer, BasicJsonType&,
        T>::value;
};


///////////////////
// is_ functions //
///////////////////

template <typename T, typename = void>
struct is_iterator_traits : std::false_type {};

template <typename T>
struct is_iterator_traits<iterator_traits<T>>
{
  private:
    using traits = iterator_traits<T>;

  public:
    static constexpr auto value =
        is_detected<value_type_t, traits>::value &&
        is_detected<difference_type_t, traits>::value &&
        is_detected<pointer_t, traits>::value &&
        is_detected<iterator_category_t, traits>::value &&
        is_detected<reference_t, traits>::value;
};

// source: https://stackoverflow.com/a/37193089/4116453

template <typename T, typename = void>
struct is_complete_type : std::false_type {};

template <typename T>
struct is_complete_type<T, decltype(void(sizeof(T)))> : std::true_type {};

template <typename BasicJsonType, typename CompatibleObjectType,
          typename = void>
struct is_compatible_object_type_impl : std::false_type {};

template <typename BasicJsonType, typename CompatibleObjectType>
struct is_compatible_object_type_impl <
    BasicJsonType, CompatibleObjectType,
    enable_if_t<is_detected<mapped_type_t, CompatibleObjectType>::value and
    is_detected<key_type_t, CompatibleObjectType>::value >>
{

    using object_t = typename BasicJsonType::object_t;

    // macOS's is_constructible does not play well with nonesuch...
    static constexpr bool value =
        std::is_constructible<typename object_t::key_type,
        typename CompatibleObjectType::key_type>::value and
        std::is_constructible<typename object_t::mapped_type,
        typename CompatibleObjectType::mapped_type>::value;
};

template <typename BasicJsonType, typename CompatibleObjectType>
struct is_compatible_object_type
    : is_compatible_object_type_impl<BasicJsonType, CompatibleObjectType> {};

template <typename BasicJsonType, typename ConstructibleObjectType,
          typename = void>
struct is_constructible_object_type_impl : std::false_type {};

template <typename BasicJsonType, typename ConstructibleObjectType>
struct is_constructible_object_type_impl <
    BasicJsonType, ConstructibleObjectType,
    enable_if_t<is_detected<mapped_type_t, ConstructibleObjectType>::value and
    is_detected<key_type_t, ConstructibleObjectType>::value >>
{
    using object_t = typename BasicJsonType::object_t;

    static constexpr bool value =
        (std::is_constructible<typename ConstructibleObjectType::key_type, typename object_t::key_type>::value and
         std::is_same<typename object_t::mapped_type, typename ConstructibleObjectType::mapped_type>::value) or
        (has_from_json<BasicJsonType, typename ConstructibleObjectType::mapped_type>::value or
         has_non_default_from_json<BasicJsonType, typename ConstructibleObjectType::mapped_type >::value);
};

template <typename BasicJsonType, typename ConstructibleObjectType>
struct is_constructible_object_type
    : is_constructible_object_type_impl<BasicJsonType,
      ConstructibleObjectType> {};

template <typename BasicJsonType, typename CompatibleStringType,
          typename = void>
struct is_compatible_string_type_impl : std::false_type {};

template <typename BasicJsonType, typename CompatibleStringType>
struct is_compatible_string_type_impl <
    BasicJsonType, CompatibleStringType,
    enable_if_t<is_detected_exact<typename BasicJsonType::string_t::value_type,
    value_type_t, CompatibleStringType>::value >>
{
    static constexpr auto value =
        std::is_constructible<typename BasicJsonType::string_t, CompatibleStringType>::value;
};

template <typename BasicJsonType, typename ConstructibleStringType>
struct is_compatible_string_type
    : is_compatible_string_type_impl<BasicJsonType, ConstructibleStringType> {};

template <typename BasicJsonType, typename ConstructibleStringType,
          typename = void>
struct is_constructible_string_type_impl : std::false_type {};

template <typename BasicJsonType, typename ConstructibleStringType>
struct is_constructible_string_type_impl <
    BasicJsonType, ConstructibleStringType,
    enable_if_t<is_detected_exact<typename BasicJsonType::string_t::value_type,
    value_type_t, ConstructibleStringType>::value >>
{
    static constexpr auto value =
        std::is_constructible<ConstructibleStringType,
        typename BasicJsonType::string_t>::value;
};

template <typename BasicJsonType, typename ConstructibleStringType>
struct is_constructible_string_type
    : is_constructible_string_type_impl<BasicJsonType, ConstructibleStringType> {};

template <typename BasicJsonType, typename CompatibleArrayType, typename = void>
struct is_compatible_array_type_impl : std::false_type {};

template <typename BasicJsonType, typename CompatibleArrayType>
struct is_compatible_array_type_impl <
    BasicJsonType, CompatibleArrayType,
    enable_if_t<is_detected<value_type_t, CompatibleArrayType>::value and
    is_detected<iterator_t, CompatibleArrayType>::value and
// This is needed because json_reverse_iterator has a ::iterator type...
// Therefore it is detected as a CompatibleArrayType.
// The real fix would be to have an Iterable concept.
    not is_iterator_traits<
    iterator_traits<CompatibleArrayType>>::value >>
{
    static constexpr bool value =
        std::is_constructible<BasicJsonType,
        typename CompatibleArrayType::value_type>::value;
};

template <typename BasicJsonType, typename CompatibleArrayType>
struct is_compatible_array_type
    : is_compatible_array_type_impl<BasicJsonType, CompatibleArrayType> {};

template <typename BasicJsonType, typename ConstructibleArrayType, typename = void>
struct is_constructible_array_type_impl : std::false_type {};

template <typename BasicJsonType, typename ConstructibleArrayType>
struct is_constructible_array_type_impl <
    BasicJsonType, ConstructibleArrayType,
    enable_if_t<std::is_same<ConstructibleArrayType,
    typename BasicJsonType::value_type>::value >>
            : std::true_type {};

template <typename BasicJsonType, typename ConstructibleArrayType>
struct is_constructible_array_type_impl <
    BasicJsonType, ConstructibleArrayType,
    enable_if_t<not std::is_same<ConstructibleArrayType,
    typename BasicJsonType::value_type>::value and
    is_detected<value_type_t, ConstructibleArrayType>::value and
    is_detected<iterator_t, ConstructibleArrayType>::value and
    is_complete_type<
    detected_t<value_type_t, ConstructibleArrayType>>::value >>
{
    static constexpr bool value =
        // This is needed because json_reverse_iterator has a ::iterator type,
        // furthermore, std::back_insert_iterator (and other iterators) have a base class `iterator`...
        // Therefore it is detected as a ConstructibleArrayType.
        // The real fix would be to have an Iterable concept.
        not is_iterator_traits <
        iterator_traits<ConstructibleArrayType >>::value and

        (std::is_same<typename ConstructibleArrayType::value_type, typename BasicJsonType::array_t::value_type>::value or
         has_from_json<BasicJsonType,
         typename ConstructibleArrayType::value_type>::value or
         has_non_default_from_json <
         BasicJsonType, typename ConstructibleArrayType::value_type >::value);
};

template <typename BasicJsonType, typename ConstructibleArrayType>
struct is_constructible_array_type
    : is_constructible_array_type_impl<BasicJsonType, ConstructibleArrayType> {};

template <typename RealIntegerType, typename CompatibleNumberIntegerType,
          typename = void>
struct is_compatible_integer_type_impl : std::false_type {};

template <typename RealIntegerType, typename CompatibleNumberIntegerType>
struct is_compatible_integer_type_impl <
    RealIntegerType, CompatibleNumberIntegerType,
    enable_if_t<std::is_integral<RealIntegerType>::value and
    std::is_integral<CompatibleNumberIntegerType>::value and
    not std::is_same<bool, CompatibleNumberIntegerType>::value >>
{
    // is there an assert somewhere on overflows?
    using RealLimits = std::numeric_limits<RealIntegerType>;
    using CompatibleLimits = std::numeric_limits<CompatibleNumberIntegerType>;

    static constexpr auto value =
        std::is_constructible<RealIntegerType,
        CompatibleNumberIntegerType>::value and
        CompatibleLimits::is_integer and
        RealLimits::is_signed == CompatibleLimits::is_signed;
};

template <typename RealIntegerType, typename CompatibleNumberIntegerType>
struct is_compatible_integer_type
    : is_compatible_integer_type_impl<RealIntegerType,
      CompatibleNumberIntegerType> {};

template <typename BasicJsonType, typename CompatibleType, typename = void>
struct is_compatible_type_impl: std::false_type {};

template <typename BasicJsonType, typename CompatibleType>
struct is_compatible_type_impl <
    BasicJsonType, CompatibleType,
    enable_if_t<is_complete_type<CompatibleType>::value >>
{
    static constexpr bool value =
        has_to_json<BasicJsonType, CompatibleType>::value;
};

template <typename BasicJsonType, typename CompatibleType>
struct is_compatible_type
    : is_compatible_type_impl<BasicJsonType, CompatibleType> {};
}  // namespace detail
}  // namespace nlohmann

// #include <nlohmann/detail/value_t.hpp>


#include <array> // array
#include <ciso646> // and
#include <cstddef> // size_t
#include <cstdint> // uint8_t
#include <string> // string

namespace nlohmann
{
namespace detail
{
///////////////////////////
// JSON type enumeration //
///////////////////////////

/*!
@brief the JSON type enumeration

This enumeration collects the different JSON types. It is internally used to
distinguish the stored values, and the functions @ref basic_json::is_null(),
@ref basic_json::is_object(), @ref basic_json::is_array(),
@ref basic_json::is_string(), @ref basic_json::is_boolean(),
@ref basic_json::is_number() (with @ref basic_json::is_number_integer(),
@ref basic_json::is_number_unsigned(), and @ref basic_json::is_number_float()),
@ref basic_json::is_discarded(), @ref basic_json::is_primitive(), and
@ref basic_json::is_structured() rely on it.

@note There are three enumeration entries (number_integer, number_unsigned, and
number_float), because the library distinguishes these three types for numbers:
@ref basic_json::number_unsigned_t is used for unsigned integers,
@ref basic_json::number_integer_t is used for signed integers, and
@ref basic_json::number_float_t is used for floating-point numbers or to
approximate integers which do not fit in the limits of their respective type.

@sa @ref basic_json::basic_json(const value_t value_type) -- create a JSON
value with the default value for a given type

@since version 1.0.0
*/
enum class value_t : std::uint8_t
{
    null,             ///< null value
    object,           ///< object (unordered set of name/value pairs)
    array,            ///< array (ordered collection of values)
    string,           ///< string value
    boolean,          ///< boolean value
    number_integer,   ///< number value (signed integer)
    number_unsigned,  ///< number value (unsigned integer)
    number_float,     ///< number value (floating-point)
    discarded         ///< discarded by the the parser callback function
};

/*!
@brief comparison operator for JSON types

Returns an ordering that is similar to Python:
- order: null < boolean < number < object < array < string
- furthermore, each type is not smaller than itself
- discarded values are not comparable

@since version 1.0.0
*/
inline bool operator<(const value_t lhs, const value_t rhs) noexcept
{
    static constexpr std::array<std::uint8_t, 8> order = {{
            0 /* null */, 3 /* object */, 4 /* array */, 5 /* string */,
            1 /* boolean */, 2 /* integer */, 2 /* unsigned */, 2 /* float */
        }
    };

    const auto l_index = static_cast<std::size_t>(lhs);
    const auto r_index = static_cast<std::size_t>(rhs);
    return l_index < order.size() and r_index < order.size() and order[l_index] < order[r_index];
}
}  // namespace detail
}  // namespace nlohmann


namespace nlohmann
{
namespace detail
{
template<typename BasicJsonType>
void from_json(const BasicJsonType& j, typename std::nullptr_t& n)
{
    if (JSON_UNLIKELY(not j.is_null()))
    {
        JSON_THROW(type_error::create(302, "type must be null, but is " + std::string(j.type_name())));
    }
    n = nullptr;
}

// overloads for basic_json template parameters
template<typename BasicJsonType, typename ArithmeticType,
         enable_if_t<std::is_arithmetic<ArithmeticType>::value and
                     not std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value,
                     int> = 0>
void get_arithmetic_value(const BasicJsonType& j, ArithmeticType& val)
{
    switch (static_cast<value_t>(j))
    {
        case value_t::number_unsigned:
        {
            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>());
            break;
        }
        case value_t::number_integer:
        {
            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>());
            break;
        }
        case value_t::number_float:
        {
            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>());
            break;
        }

        default:
            JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name())));
    }
}

template<typename BasicJsonType>
void from_json(const BasicJsonType& j, typename BasicJsonType::boolean_t& b)
{
    if (JSON_UNLIKELY(not j.is_boolean()))
    {
        JSON_THROW(type_error::create(302, "type must be boolean, but is " + std::string(j.type_name())));
    }
    b = *j.template get_ptr<const typename BasicJsonType::boolean_t*>();
}

template<typename BasicJsonType>
void from_json(const BasicJsonType& j, typename BasicJsonType::string_t& s)
{
    if (JSON_UNLIKELY(not j.is_string()))
    {
        JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name())));
    }
    s = *j.template get_ptr<const typename BasicJsonType::string_t*>();
}

template <
    typename BasicJsonType, typename ConstructibleStringType,
    enable_if_t <
        is_constructible_string_type<BasicJsonType, ConstructibleStringType>::value and
        not std::is_same<typename BasicJsonType::string_t,
                         ConstructibleStringType>::value,
        int > = 0 >
void from_json(const BasicJsonType& j, ConstructibleStringType& s)
{
    if (JSON_UNLIKELY(not j.is_string()))
    {
        JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name())));
    }

    s = *j.template get_ptr<const typename BasicJsonType::string_t*>();
}

template<typename BasicJsonType>
void from_json(const BasicJsonType& j, typename BasicJsonType::number_float_t& val)
{
    get_arithmetic_value(j, val);
}

template<typename BasicJsonType>
void from_json(const BasicJsonType& j, typename BasicJsonType::number_unsigned_t& val)
{
    get_arithmetic_value(j, val);
}

template<typename BasicJsonType>
void from_json(const BasicJsonType& j, typename BasicJsonType::number_integer_t& val)
{
    get_arithmetic_value(j, val);
}

template<typename BasicJsonType, typename EnumType,
         enable_if_t<std::is_enum<EnumType>::value, int> = 0>
void from_json(const BasicJsonType& j, EnumType& e)
{
    typename std::underlying_type<EnumType>::type val;
    get_arithmetic_value(j, val);
    e = static_cast<EnumType>(val);
}

// forward_list doesn't have an insert method
template<typename BasicJsonType, typename T, typename Allocator,
         enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
void from_json(const BasicJsonType& j, std::forward_list<T, Allocator>& l)
{
    if (JSON_UNLIKELY(not j.is_array()))
    {
        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
    }
    std::transform(j.rbegin(), j.rend(),
                   std::front_inserter(l), [](const BasicJsonType & i)
    {
        return i.template get<T>();
    });
}

// valarray doesn't have an insert method
template<typename BasicJsonType, typename T,
         enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
void from_json(const BasicJsonType& j, std::valarray<T>& l)
{
    if (JSON_UNLIKELY(not j.is_array()))
    {
        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
    }
    l.resize(j.size());
    std::copy(j.m_value.array->begin(), j.m_value.array->end(), std::begin(l));
}

template<typename BasicJsonType>
void from_json_array_impl(const BasicJsonType& j, typename BasicJsonType::array_t& arr, priority_tag<3> /*unused*/)
{
    arr = *j.template get_ptr<const typename BasicJsonType::array_t*>();
}

template <typename BasicJsonType, typename T, std::size_t N>
auto from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr,
                          priority_tag<2> /*unused*/)
-> decltype(j.template get<T>(), void())
{
    for (std::size_t i = 0; i < N; ++i)
    {
        arr[i] = j.at(i).template get<T>();
    }
}

template<typename BasicJsonType, typename ConstructibleArrayType>
auto from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr, priority_tag<1> /*unused*/)
-> decltype(
    arr.reserve(std::declval<typename ConstructibleArrayType::size_type>()),
    j.template get<typename ConstructibleArrayType::value_type>(),
    void())
{
    using std::end;

    arr.reserve(j.size());
    std::transform(j.begin(), j.end(),
                   std::inserter(arr, end(arr)), [](const BasicJsonType & i)
    {
        // get<BasicJsonType>() returns *this, this won't call a from_json
        // method when value_type is BasicJsonType
        return i.template get<typename ConstructibleArrayType::value_type>();
    });
}

template <typename BasicJsonType, typename ConstructibleArrayType>
void from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr,
                          priority_tag<0> /*unused*/)
{
    using std::end;

    std::transform(
        j.begin(), j.end(), std::inserter(arr, end(arr)),
        [](const BasicJsonType & i)
    {
        // get<BasicJsonType>() returns *this, this won't call a from_json
        // method when value_type is BasicJsonType
        return i.template get<typename ConstructibleArrayType::value_type>();
    });
}

template <typename BasicJsonType, typename ConstructibleArrayType,
          enable_if_t <
              is_constructible_array_type<BasicJsonType, ConstructibleArrayType>::value and
              not is_constructible_object_type<BasicJsonType, ConstructibleArrayType>::value and
              not is_constructible_string_type<BasicJsonType, ConstructibleArrayType>::value and
              not is_basic_json<ConstructibleArrayType>::value,
              int > = 0 >

auto from_json(const BasicJsonType& j, ConstructibleArrayType& arr)
-> decltype(from_json_array_impl(j, arr, priority_tag<3> {}),
j.template get<typename ConstructibleArrayType::value_type>(),
void())
{
    if (JSON_UNLIKELY(not j.is_array()))
    {
        JSON_THROW(type_error::create(302, "type must be array, but is " +
                                      std::string(j.type_name())));
    }

    from_json_array_impl(j, arr, priority_tag<3> {});
}

template<typename BasicJsonType, typename ConstructibleObjectType,
         enable_if_t<is_constructible_object_type<BasicJsonType, ConstructibleObjectType>::value, int> = 0>
void from_json(const BasicJsonType& j, ConstructibleObjectType& obj)
{
    if (JSON_UNLIKELY(not j.is_object()))
    {
        JSON_THROW(type_error::create(302, "type must be object, but is " + std::string(j.type_name())));
    }

    auto inner_object = j.template get_ptr<const typename BasicJsonType::object_t*>();
    using value_type = typename ConstructibleObjectType::value_type;
    std::transform(
        inner_object->begin(), inner_object->end(),
        std::inserter(obj, obj.begin()),
        [](typename BasicJsonType::object_t::value_type const & p)
    {
        return value_type(p.first, p.second.template get<typename ConstructibleObjectType::mapped_type>());
    });
}

// overload for arithmetic types, not chosen for basic_json template arguments
// (BooleanType, etc..); note: Is it really necessary to provide explicit
// overloads for boolean_t etc. in case of a custom BooleanType which is not
// an arithmetic type?
template<typename BasicJsonType, typename ArithmeticType,
         enable_if_t <
             std::is_arithmetic<ArithmeticType>::value and
             not std::is_same<ArithmeticType, typename BasicJsonType::number_unsigned_t>::value and
             not std::is_same<ArithmeticType, typename BasicJsonType::number_integer_t>::value and
             not std::is_same<ArithmeticType, typename BasicJsonType::number_float_t>::value and
             not std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value,
             int> = 0>
void from_json(const BasicJsonType& j, ArithmeticType& val)
{
    switch (static_cast<value_t>(j))
    {
        case value_t::number_unsigned:
        {
            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>());
            break;
        }
        case value_t::number_integer:
        {
            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>());
            break;
        }
        case value_t::number_float:
        {
            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>());
            break;
        }
        case value_t::boolean:
        {
            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::boolean_t*>());
            break;
        }

        default:
            JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name())));
    }
}

template<typename BasicJsonType, typename A1, typename A2>
void from_json(const BasicJsonType& j, std::pair<A1, A2>& p)
{
    p = {j.at(0).template get<A1>(), j.at(1).template get<A2>()};
}

template<typename BasicJsonType, typename Tuple, std::size_t... Idx>
void from_json_tuple_impl(const BasicJsonType& j, Tuple& t, index_sequence<Idx...> /*unused*/)
{
    t = std::make_tuple(j.at(Idx).template get<typename std::tuple_element<Idx, Tuple>::type>()...);
}

template<typename BasicJsonType, typename... Args>
void from_json(const BasicJsonType& j, std::tuple<Args...>& t)
{
    from_json_tuple_impl(j, t, index_sequence_for<Args...> {});
}

template <typename BasicJsonType, typename Key, typename Value, typename Compare, typename Allocator,
          typename = enable_if_t<not std::is_constructible<
                                     typename BasicJsonType::string_t, Key>::value>>
void from_json(const BasicJsonType& j, std::map<Key, Value, Compare, Allocator>& m)
{
    if (JSON_UNLIKELY(not j.is_array()))
    {
        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
    }
    for (const auto& p : j)
    {
        if (JSON_UNLIKELY(not p.is_array()))
        {
            JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(p.type_name())));
        }
        m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
    }
}

template <typename BasicJsonType, typename Key, typename Value, typename Hash, typename KeyEqual, typename Allocator,
          typename = enable_if_t<not std::is_constructible<
                                     typename BasicJsonType::string_t, Key>::value>>
void from_json(const BasicJsonType& j, std::unordered_map<Key, Value, Hash, KeyEqual, Allocator>& m)
{
    if (JSON_UNLIKELY(not j.is_array()))
    {
        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
    }
    for (const auto& p : j)
    {
        if (JSON_UNLIKELY(not p.is_array()))
        {
            JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(p.type_name())));
        }
        m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
    }
}

struct from_json_fn
{
    template<typename BasicJsonType, typename T>
    auto operator()(const BasicJsonType& j, T& val) const
    noexcept(noexcept(from_json(j, val)))
    -> decltype(from_json(j, val), void())
    {
        return from_json(j, val);
    }
};
}  // namespace detail

/// namespace to hold default `from_json` function
/// to see why this is required:
/// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4381.html
namespace
{
constexpr const auto& from_json = detail::static_const<detail::from_json_fn>::value;
} // namespace
}  // namespace nlohmann

// #include <nlohmann/detail/conversions/to_json.hpp>


#include <algorithm> // copy
#include <ciso646> // or, and, not
#include <iterator> // begin, end
#include <string> // string
#include <tuple> // tuple, get
#include <type_traits> // is_same, is_constructible, is_floating_point, is_enum, underlying_type
#include <utility> // move, forward, declval, pair
#include <valarray> // valarray
#include <vector> // vector

// #include <nlohmann/detail/iterators/iteration_proxy.hpp>


#include <cstddef> // size_t
#include <iterator> // input_iterator_tag
#include <string> // string, to_string
#include <tuple> // tuple_size, get, tuple_element

// #include <nlohmann/detail/meta/type_traits.hpp>

// #include <nlohmann/detail/value_t.hpp>


namespace nlohmann
{
namespace detail
{
template <typename IteratorType> class iteration_proxy_value
{
  public:
    using difference_type = std::ptrdiff_t;
    using value_type = iteration_proxy_value;
    using pointer = value_type * ;
    using reference = value_type & ;
    using iterator_category = std::input_iterator_tag;

  private:
    /// the iterator
    IteratorType anchor;
    /// an index for arrays (used to create key names)
    std::size_t array_index = 0;
    /// last stringified array index
    mutable std::size_t array_index_last = 0;
    /// a string representation of the array index
    mutable std::string array_index_str = "0";
    /// an empty string (to return a reference for primitive values)
    const std::string empty_str = "";

  public:
    explicit iteration_proxy_value(IteratorType it) noexcept : anchor(it) {}

    /// dereference operator (needed for range-based for)
    iteration_proxy_value& operator*()
    {
        return *this;
    }

    /// increment operator (needed for range-based for)
    iteration_proxy_value& operator++()
    {
        ++anchor;
        ++array_index;

        return *this;
    }

    /// equality operator (needed for InputIterator)
    bool operator==(const iteration_proxy_value& o) const
    {
        return anchor == o.anchor;
    }

    /// inequality operator (needed for range-based for)
    bool operator!=(const iteration_proxy_value& o) const
    {
        return anchor != o.anchor;
    }

    /// return key of the iterator
    const std::string& key() const
    {
        assert(anchor.m_object != nullptr);

        switch (anchor.m_object->type())
        {
            // use integer array index as key
            case value_t::array:
            {
                if (array_index != array_index_last)
                {
                    array_index_str = std::to_string(array_index);
                    array_index_last = array_index;
                }
                return array_index_str;
            }

            // use key from the object
            case value_t::object:
                return anchor.key();

            // use an empty key for all primitive types
            default:
                return empty_str;
        }
    }

    /// return value of the iterator
    typename IteratorType::reference value() const
    {
        return anchor.value();
    }
};

/// proxy class for the items() function
template<typename IteratorType> class iteration_proxy
{
  private:
    /// the container to iterate
    typename IteratorType::reference container;

  public:
    /// construct iteration proxy from a container
    explicit iteration_proxy(typename IteratorType::reference cont) noexcept
        : container(cont) {}

    /// return iterator begin (needed for range-based for)
    iteration_proxy_value<IteratorType> begin() noexcept
    {
        return iteration_proxy_value<IteratorType>(container.begin());
    }

    /// return iterator end (needed for range-based for)
    iteration_proxy_value<IteratorType> end() noexcept
    {
        return iteration_proxy_value<IteratorType>(container.end());
    }
};
// Structured Bindings Support
// For further reference see https://blog.tartanllama.xyz/structured-bindings/
// And see https://github.com/nlohmann/json/pull/1391
template <std::size_t N, typename IteratorType, enable_if_t<N == 0, int> = 0>
auto get(const nlohmann::detail::iteration_proxy_value<IteratorType>& i) -> decltype(i.key())
{
    return i.key();
}
// Structured Bindings Support
// For further reference see https://blog.tartanllama.xyz/structured-bindings/
// And see https://github.com/nlohmann/json/pull/1391
template <std::size_t N, typename IteratorType, enable_if_t<N == 1, int> = 0>
auto get(const nlohmann::detail::iteration_proxy_value<IteratorType>& i) -> decltype(i.value())
{
    return i.value();
}
}  // namespace detail
}  // namespace nlohmann

// The Addition to the STD Namespace is required to add
// Structured Bindings Support to the iteration_proxy_value class
// For further reference see https://blog.tartanllama.xyz/structured-bindings/
// And see https://github.com/nlohmann/json/pull/1391
namespace std
{
#if defined(__clang__)
    // Fix: https://github.com/nlohmann/json/issues/1401
    #pragma clang diagnostic push
    #pragma clang diagnostic ignored "-Wmismatched-tags"
#endif
template <typename IteratorType>
class tuple_size<::nlohmann::detail::iteration_proxy_value<IteratorType>>
            : public std::integral_constant<std::size_t, 2> {};

template <std::size_t N, typename IteratorType>
class tuple_element<N, ::nlohmann::detail::iteration_proxy_value<IteratorType >>
{
  public:
    using type = decltype(
                     get<N>(std::declval <
                            ::nlohmann::detail::iteration_proxy_value<IteratorType >> ()));
};
#if defined(__clang__)
    #pragma clang diagnostic pop
#endif
} // namespace std

// #include <nlohmann/detail/meta/cpp_future.hpp>

// #include <nlohmann/detail/meta/type_traits.hpp>

// #include <nlohmann/detail/value_t.hpp>


namespace nlohmann
{
namespace detail
{
//////////////////
// constructors //
//////////////////

template<value_t> struct external_constructor;

template<>
struct external_constructor<value_t::boolean>
{
    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, typename BasicJsonType::boolean_t b) noexcept
    {
        j.m_type = value_t::boolean;
        j.m_value = b;
        j.assert_invariant();
    }
};

template<>
struct external_constructor<value_t::string>
{
    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, const typename BasicJsonType::string_t& s)
    {
        j.m_type = value_t::string;
        j.m_value = s;
        j.assert_invariant();
    }

    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, typename BasicJsonType::string_t&& s)
    {
        j.m_type = value_t::string;
        j.m_value = std::move(s);
        j.assert_invariant();
    }

    template<typename BasicJsonType, typename CompatibleStringType,
             enable_if_t<not std::is_same<CompatibleStringType, typename BasicJsonType::string_t>::value,
                         int> = 0>
    static void construct(BasicJsonType& j, const CompatibleStringType& str)
    {
        j.m_type = value_t::string;
        j.m_value.string = j.template create<typename BasicJsonType::string_t>(str);
        j.assert_invariant();
    }
};

template<>
struct external_constructor<value_t::number_float>
{
    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, typename BasicJsonType::number_float_t val) noexcept
    {
        j.m_type = value_t::number_float;
        j.m_value = val;
        j.assert_invariant();
    }
};

template<>
struct external_constructor<value_t::number_unsigned>
{
    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, typename BasicJsonType::number_unsigned_t val) noexcept
    {
        j.m_type = value_t::number_unsigned;
        j.m_value = val;
        j.assert_invariant();
    }
};

template<>
struct external_constructor<value_t::number_integer>
{
    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, typename BasicJsonType::number_integer_t val) noexcept
    {
        j.m_type = value_t::number_integer;
        j.m_value = val;
        j.assert_invariant();
    }
};

template<>
struct external_constructor<value_t::array>
{
    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, const typename BasicJsonType::array_t& arr)
    {
        j.m_type = value_t::array;
        j.m_value = arr;
        j.assert_invariant();
    }

    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
    {
        j.m_type = value_t::array;
        j.m_value = std::move(arr);
        j.assert_invariant();
    }

    template<typename BasicJsonType, typename CompatibleArrayType,
             enable_if_t<not std::is_same<CompatibleArrayType, typename BasicJsonType::array_t>::value,
                         int> = 0>
    static void construct(BasicJsonType& j, const CompatibleArrayType& arr)
    {
        using std::begin;
        using std::end;
        j.m_type = value_t::array;
        j.m_value.array = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr));
        j.assert_invariant();
    }

    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, const std::vector<bool>& arr)
    {
        j.m_type = value_t::array;
        j.m_value = value_t::array;
        j.m_value.array->reserve(arr.size());
        for (const bool x : arr)
        {
            j.m_value.array->push_back(x);
        }
        j.assert_invariant();
    }

    template<typename BasicJsonType, typename T,
             enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
    static void construct(BasicJsonType& j, const std::valarray<T>& arr)
    {
        j.m_type = value_t::array;
        j.m_value = value_t::array;
        j.m_value.array->resize(arr.size());
        std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
        j.assert_invariant();
    }
};

template<>
struct external_constructor<value_t::object>
{
    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, const typename BasicJsonType::object_t& obj)
    {
        j.m_type = value_t::object;
        j.m_value = obj;
        j.assert_invariant();
    }

    template<typename BasicJsonType>
    static void construct(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
    {
        j.m_type = value_t::object;
        j.m_value = std::move(obj);
        j.assert_invariant();
    }

    template<typename BasicJsonType, typename CompatibleObjectType,
             enable_if_t<not std::is_same<CompatibleObjectType, typename BasicJsonType::object_t>::value, int> = 0>
    static void construct(BasicJsonType& j, const CompatibleObjectType& obj)
    {
        using std::begin;
        using std::end;

        j.m_type = value_t::object;
        j.m_value.object = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj));
        j.assert_invariant();
    }
};

/////////////
// to_json //
/////////////

template<typename BasicJsonType, typename T,
         enable_if_t<std::is_same<T, typename BasicJsonType::boolean_t>::value, int> = 0>
void to_json(BasicJsonType& j, T b) noexcept
{
    external_constructor<value_t::boolean>::construct(j, b);
}

template<typename BasicJsonType, typename CompatibleString,
         enable_if_t<std::is_constructible<typename BasicJsonType::string_t, CompatibleString>::value, int> = 0>
void to_json(BasicJsonType& j, const CompatibleString& s)
{
    external_constructor<value_t::string>::construct(j, s);
}

template<typename BasicJsonType>
void to_json(BasicJsonType& j, typename BasicJsonType::string_t&& s)
{
    external_constructor<value_t::string>::construct(j, std::move(s));
}

template<typename BasicJsonType, typename FloatType,
         enable_if_t<std::is_floating_point<FloatType>::value, int> = 0>
void to_json(BasicJsonType& j, FloatType val) noexcept
{
    external_constructor<value_t::number_float>::construct(j, static_cast<typename BasicJsonType::number_float_t>(val));
}

template<typename BasicJsonType, typename CompatibleNumberUnsignedType,
         enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_unsigned_t, CompatibleNumberUnsignedType>::value, int> = 0>
void to_json(BasicJsonType& j, CompatibleNumberUnsignedType val) noexcept
{
    external_constructor<value_t::number_unsigned>::construct(j, static_cast<typename BasicJsonType::number_unsigned_t>(val));
}

template<typename BasicJsonType, typename CompatibleNumberIntegerType,
         enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_integer_t, CompatibleNumberIntegerType>::value, int> = 0>
void to_json(BasicJsonType& j, CompatibleNumberIntegerType val) noexcept
{
    external_constructor<value_t::number_integer>::construct(j, static_cast<typename BasicJsonType::number_integer_t>(val));
}

template<typename BasicJsonType, typename EnumType,
         enable_if_t<std::is_enum<EnumType>::value, int> = 0>
void to_json(BasicJsonType& j, EnumType e) noexcept
{
    using underlying_type = typename std::underlying_type<EnumType>::type;
    external_constructor<value_t::number_integer>::construct(j, static_cast<underlying_type>(e));
}

template<typename BasicJsonType>
void to_json(BasicJsonType& j, const std::vector<bool>& e)
{
    external_constructor<value_t::array>::construct(j, e);
}

template <typename BasicJsonType, typename CompatibleArrayType,
          enable_if_t<is_compatible_array_type<BasicJsonType,
                      CompatibleArrayType>::value and
                      not is_compatible_object_type<
                          BasicJsonType, CompatibleArrayType>::value and
                      not is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value and
                      not is_basic_json<CompatibleArrayType>::value,
                      int> = 0>
void to_json(BasicJsonType& j, const CompatibleArrayType& arr)
{
    external_constructor<value_t::array>::construct(j, arr);
}

template<typename BasicJsonType, typename T,
         enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
void to_json(BasicJsonType& j, const std::valarray<T>& arr)
{
    external_constructor<value_t::array>::construct(j, std::move(arr));
}

template<typename BasicJsonType>
void to_json(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
{
    external_constructor<value_t::array>::construct(j, std::move(arr));
}

template<typename BasicJsonType, typename CompatibleObjectType,
         enable_if_t<is_compatible_object_type<BasicJsonType, CompatibleObjectType>::value and not is_basic_json<CompatibleObjectType>::value, int> = 0>
void to_json(BasicJsonType& j, const CompatibleObjectType& obj)
{
    external_constructor<value_t::object>::construct(j, obj);
}

template<typename BasicJsonType>
void to_json(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
{
    external_constructor<value_t::object>::construct(j, std::move(obj));
}

template <
    typename BasicJsonType, typename T, std::size_t N,
    enable_if_t<not std::is_constructible<typename BasicJsonType::string_t,
                const T(&)[N]>::value,
                int> = 0 >
void to_json(BasicJsonType& j, const T(&arr)[N])
{
    external_constructor<value_t::array>::construct(j, arr);
}

template<typename BasicJsonType, typename... Args>
void to_json(BasicJsonType& j, const std::pair<Args...>& p)
{
    j = { p.first, p.second };
}

// for https://github.com/nlohmann/json/pull/1134
template < typename BasicJsonType, typename T,
           enable_if_t<std::is_same<T, iteration_proxy_value<typename BasicJsonType::iterator>>::value, int> = 0>
void to_json(BasicJsonType& j, const T& b)
{
    j = { {b.key(), b.value()} };
}

template<typename BasicJsonType, typename Tuple, std::size_t... Idx>
void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<Idx...> /*unused*/)
{
    j = { std::get<Idx>(t)... };
}

template<typename BasicJsonType, typename... Args>
void to_json(BasicJsonType& j, const std::tuple<Args...>& t)
{
    to_json_tuple_impl(j, t, index_sequence_for<Args...> {});
}

struct to_json_fn
{
    template<typename BasicJsonType, typename T>
    auto operator()(BasicJsonType& j, T&& val) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
    -> decltype(to_json(j, std::forward<T>(val)), void())
    {
        return to_json(j, std::forward<T>(val));
    }
};
}  // namespace detail

/// namespace to hold default `to_json` function
namespace
{
constexpr const auto& to_json = detail::static_const<detail::to_json_fn>::value;
} // namespace
}  // namespace nlohmann


namespace nlohmann
{

template<typename, typename>
struct adl_serializer
{
    /*!
    @brief convert a JSON value to any value type

    This function is usually called by the `get()` function of the
    @ref basic_json class (either explicit or via conversion operators).

    @param[in] j        JSON value to read from
    @param[in,out] val  value to write to
    */
    template<typename BasicJsonType, typename ValueType>
    static auto from_json(BasicJsonType&& j, ValueType& val) noexcept(
        noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val)))
    -> decltype(::nlohmann::from_json(std::forward<BasicJsonType>(j), val), void())
    {
        ::nlohmann::from_json(std::forward<BasicJsonType>(j), val);
    }

    /*!
    @brief convert any value type to a JSON value

    This function is usually called by the constructors of the @ref basic_json
    class.

    @param[in,out] j  JSON value to write to
    @param[in] val    value to read from
    */
    template <typename BasicJsonType, typename ValueType>
    static auto to_json(BasicJsonType& j, ValueType&& val) noexcept(
        noexcept(::nlohmann::to_json(j, std::forward<ValueType>(val))))
    -> decltype(::nlohmann::to_json(j, std::forward<ValueType>(val)), void())
    {
        ::nlohmann::to_json(j, std::forward<ValueType>(val));
    }
};

}  // namespace nlohmann

// #include <nlohmann/detail/conversions/from_json.hpp>

// #include <nlohmann/detail/conversions/to_json.hpp>

// #include <nlohmann/detail/exceptions.hpp>

// #include <nlohmann/detail/input/binary_reader.hpp>


#include <algorithm> // generate_n
#include <array> // array
#include <cassert> // assert
#include <cmath> // ldexp
#include <cstddef> // size_t
#include <cstdint> // uint8_t, uint16_t, uint32_t, uint64_t
#include <cstdio> // snprintf
#include <cstring> // memcpy
#include <iterator> // back_inserter
#include <limits> // numeric_limits
#include <string> // char_traits, string
#include <utility> // make_pair, move

// #include <nlohmann/detail/exceptions.hpp>

// #include <nlohmann/detail/input/input_adapters.hpp>


#include <array> // array
#include <cassert> // assert
#include <cstddef> // size_t
#include <cstdio> //FILE *
#include <cstring> // strlen
#include <istream> // istream
#include <iterator> // begin, end, iterator_traits, random_access_iterator_tag, distance, next
#include <memory> // shared_ptr, make_shared, addressof
#include <numeric> // accumulate
#include <string> // string, char_traits
#include <type_traits> // enable_if, is_base_of, is_pointer, is_integral, remove_pointer
#include <utility> // pair, declval

// #include <nlohmann/detail/iterators/iterator_traits.hpp>

// #include <nlohmann/detail/macro_scope.hpp>


namespace nlohmann
{
namespace detail
{
/// the supported input formats
enum class input_format_t { json, cbor, msgpack, ubjson, bson };

////////////////////
// input adapters //
////////////////////

/*!
@brief abstract input adapter interface

Produces a stream of std::char_traits<char>::int_type characters from a
std::istream, a buffer, or some other input type. Accepts the return of
exactly one non-EOF character for future input. The int_type characters
returned consist of all valid char values as positive values (typically
unsigned char), plus an EOF value outside that range, specified by the value
of the function std::char_traits<char>::eof(). This value is typically -1, but
could be any arbitrary value which is not a valid char value.
*/
struct input_adapter_protocol
{
    /// get a character [0,255] or std::char_traits<char>::eof().
    virtual std::char_traits<char>::int_type get_character() = 0;
    virtual ~input_adapter_protocol() = default;
};

/// a type to simplify interfaces
using input_adapter_t = std::shared_ptr<input_adapter_protocol>;

/*!
Input adapter for stdio file access. This adapter read only 1 byte and do not use any
 buffer. This adapter is a very low level adapter.
*/
class file_input_adapter : public input_adapter_protocol
{
  public:
    explicit file_input_adapter(std::FILE* f)  noexcept
        : m_file(f)
    {}

    // make class move-only
    file_input_adapter(const file_input_adapter&) = delete;
    file_input_adapter(file_input_adapter&&) = default;
    file_input_adapter& operator=(const file_input_adapter&) = delete;
    file_input_adapter& operator=(file_input_adapter&&) = default;
    ~file_input_adapter() override = default;

    std::char_traits<char>::int_type get_character() noexcept override
    {
        return std::fgetc(m_file);
    }

  private:
    /// the file pointer to read from
    std::FILE* m_file;
};


/*!
Input adapter for a (caching) istream. Ignores a UFT Byte Order Mark at
beginning of input. Does not support changing the underlying std::streambuf
in mid-input. Maintains underlying std::istream and std::streambuf to support
subsequent use of standard std::istream operations to process any input
characters following those used in parsing the JSON input.  Clears the
std::istream flags; any input errors (e.g., EOF) will be detected by the first
subsequent call for input from the std::istream.
*/
class input_stream_adapter : public input_adapter_protocol
{
  public:
    ~input_stream_adapter() override
    {
        // clear stream flags; we use underlying streambuf I/O, do not
        // maintain ifstream flags, except eof
        is.clear(is.rdstate() & std::ios::eofbit);
    }

    explicit input_stream_adapter(std::istream& i)
        : is(i), sb(*i.rdbuf())
    {}

    // delete because of pointer members
    input_stream_adapter(const input_stream_adapter&) = delete;
    input_stream_adapter& operator=(input_stream_adapter&) = delete;
    input_stream_adapter(input_stream_adapter&&) = delete;
    input_stream_adapter& operator=(input_stream_adapter&&) = delete;

    // std::istream/std::streambuf use std::char_traits<char>::to_int_type, to
    // ensure that std::char_traits<char>::eof() and the character 0xFF do not
    // end up as the same value, eg. 0xFFFFFFFF.
    std::char_traits<char>::int_type get_character() override
    {
        auto res = sb.sbumpc();
        // set eof manually, as we don't use the istream interface.
        if (res == EOF)
        {
            is.clear(is.rdstate() | std::ios::eofbit);
        }
        return res;
    }

  private:
    /// the associated input stream
    std::istream& is;
    std::streambuf& sb;
};

/// input adapter for buffer input
class input_buffer_adapter : public input_adapter_protocol
{
  public:
    input_buffer_adapter(const char* b, const std::size_t l) noexcept
        : cursor(b), limit(b + l)
    {}

    // delete because of pointer members
    input_buffer_adapter(const input_buffer_adapter&) = delete;
    input_buffer_adapter& operator=(input_buffer_adapter&) = delete;
    input_buffer_adapter(input_buffer_adapter&&) = delete;
    input_buffer_adapter& operator=(input_buffer_adapter&&) = delete;
    ~input_buffer_adapter() override = default;

    std::char_traits<char>::int_type get_character() noexcept override
    {
        if (JSON_LIKELY(cursor < limit))
        {
            return std::char_traits<char>::to_int_type(*(cursor++));
        }

        return std::char_traits<char>::eof();
    }

  private:
    /// pointer to the current character
    const char* cursor;
    /// pointer past the last character
    const char* const limit;
};

template<typename WideStringType, size_t T>
struct wide_string_input_helper
{
    // UTF-32
    static void fill_buffer(const WideStringType& str,
                            size_t& current_wchar,
                            std::array<std::char_traits<char>::int_type, 4>& utf8_bytes,
                            size_t& utf8_bytes_index,
                            size_t& utf8_bytes_filled)
    {
        utf8_bytes_index = 0;

        if (current_wchar == str.size())
        {
            utf8_bytes[0] = std::char_traits<char>::eof();
            utf8_bytes_filled = 1;
        }
        else
        {
            // get the current character
            const auto wc = static_cast<unsigned int>(str[current_wchar++]);

            // UTF-32 to UTF-8 encoding
            if (wc < 0x80)
            {
                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(wc);
                utf8_bytes_filled = 1;
            }
            else if (wc <= 0x7FF)
            {
                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xC0u | ((wc >> 6u) & 0x1Fu));
                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | (wc & 0x3Fu));
                utf8_bytes_filled = 2;
            }
            else if (wc <= 0xFFFF)
            {
                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xE0u | ((wc >> 12u) & 0x0Fu));
                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | ((wc >> 6u) & 0x3Fu));
                utf8_bytes[2] = static_cast<std::char_traits<char>::int_type>(0x80u | (wc & 0x3Fu));
                utf8_bytes_filled = 3;
            }
            else if (wc <= 0x10FFFF)
            {
                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xF0u | ((wc >> 18u) & 0x07u));
                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | ((wc >> 12u) & 0x3Fu));
                utf8_bytes[2] = static_cast<std::char_traits<char>::int_type>(0x80u | ((wc >> 6u) & 0x3Fu));
                utf8_bytes[3] = static_cast<std::char_traits<char>::int_type>(0x80u | (wc & 0x3Fu));
                utf8_bytes_filled = 4;
            }
            else
            {
                // unknown character
                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(wc);
                utf8_bytes_filled = 1;
            }
        }
    }
};

template<typename WideStringType>
struct wide_string_input_helper<WideStringType, 2>
{
    // UTF-16
    static void fill_buffer(const WideStringType& str,
                            size_t& current_wchar,
                            std::array<std::char_traits<char>::int_type, 4>& utf8_bytes,
                            size_t& utf8_bytes_index,
                            size_t& utf8_bytes_filled)
    {
        utf8_bytes_index = 0;

        if (current_wchar == str.size())
        {
            utf8_bytes[0] = std::char_traits<char>::eof();
            utf8_bytes_filled = 1;
        }
        else
        {
            // get the current character
            const auto wc = static_cast<unsigned int>(str[current_wchar++]);

            // UTF-16 to UTF-8 encoding
            if (wc < 0x80)
            {
                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(wc);
                utf8_bytes_filled = 1;
            }
            else if (wc <= 0x7FF)
            {
                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xC0u | ((wc >> 6u)));
                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | (wc & 0x3Fu));
                utf8_bytes_filled = 2;
            }
            else if (0xD800 > wc or wc >= 0xE000)
            {
                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xE0u | ((wc >> 12u)));
                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | ((wc >> 6u) & 0x3Fu));
                utf8_bytes[2] = static_cast<std::char_traits<char>::int_type>(0x80u | (wc & 0x3Fu));
                utf8_bytes_filled = 3;
            }
            else
            {
                if (current_wchar < str.size())
                {
                    const auto wc2 = static_cast<unsigned int>(str[current_wchar++]);
                    const auto charcode = 0x10000u + (((wc & 0x3FFu) << 10u) | (wc2 & 0x3FFu));
                    utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xF0u | (charcode >> 18u));
                    utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | ((charcode >> 12u) & 0x3Fu));
                    utf8_bytes[2] = static_cast<std::char_traits<char>::int_type>(0x80u | ((charcode >> 6u) & 0x3Fu));
                    utf8_bytes[3] = static_cast<std::char_traits<char>::int_type>(0x80u | (charcode & 0x3Fu));
                    utf8_bytes_filled = 4;
                }
                else
                {
                    // unknown character
                    ++current_wchar;
                    utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(wc);
                    utf8_bytes_filled = 1;
                }
            }
        }
    }
};

template<typename WideStringType>
class wide_string_input_adapter : public input_adapter_protocol
{
  public:
    explicit wide_string_input_adapter(const WideStringType& w) noexcept
        : str(w)
    {}

    std::char_traits<char>::int_type get_character() noexcept override
    {
        // check if buffer needs to be filled
        if (utf8_bytes_index == utf8_bytes_filled)
        {
            fill_buffer<sizeof(typename WideStringType::value_type)>();

            assert(utf8_bytes_filled > 0);
            assert(utf8_bytes_index == 0);
        }

        // use buffer
        assert(utf8_bytes_filled > 0);
        assert(utf8_bytes_index < utf8_bytes_filled);
        return utf8_bytes[utf8_bytes_index++];
    }

  private:
    template<size_t T>
    void fill_buffer()
    {
        wide_string_input_helper<WideStringType, T>::fill_buffer(str, current_wchar, utf8_bytes, utf8_bytes_index, utf8_bytes_filled);
    }

    /// the wstring to process
    const WideStringType& str;

    /// index of the current wchar in str
    std::size_t current_wchar = 0;

    /// a buffer for UTF-8 bytes
    std::array<std::char_traits<char>::int_type, 4> utf8_bytes = {{0, 0, 0, 0}};

    /// index to the utf8_codes array for the next valid byte
    std::size_t utf8_bytes_index = 0;
    /// number of valid bytes in the utf8_codes array
    std::size_t utf8_bytes_filled = 0;
};

class input_adapter
{
  public:
    // native support
    input_adapter(std::FILE* file)
        : ia(std::make_shared<file_input_adapter>(file)) {}
    /// input adapter for input stream
    input_adapter(std::istream& i)
        : ia(std::make_shared<input_stream_adapter>(i)) {}

    /// input adapter for input stream
    input_adapter(std::istream&& i)
        : ia(std::make_shared<input_stream_adapter>(i)) {}

    input_adapter(const std::wstring& ws)
        : ia(std::make_shared<wide_string_input_adapter<std::wstring>>(ws)) {}

    input_adapter(const std::u16string& ws)
        : ia(std::make_shared<wide_string_input_adapter<std::u16string>>(ws)) {}

    input_adapter(const std::u32string& ws)
        : ia(std::make_shared<wide_string_input_adapter<std::u32string>>(ws)) {}

    /// input adapter for buffer
    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>
    input_adapter(CharT b, std::size_t l)
        : ia(std::make_shared<input_buffer_adapter>(reinterpret_cast<const char*>(b), l)) {}

    // derived support

    /// input adapter for string literal
    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>
    input_adapter(CharT b)
        : input_adapter(reinterpret_cast<const char*>(b),
                        std::strlen(reinterpret_cast<const char*>(b))) {}

    /// input adapter for iterator range with contiguous storage
    template<class IteratorType,
             typename std::enable_if<
                 std::is_same<typename iterator_traits<IteratorType>::iterator_category, std::random_access_iterator_tag>::value,
                 int>::type = 0>
    input_adapter(IteratorType first, IteratorType last)
    {
#ifndef NDEBUG
        // assertion to check that the iterator range is indeed contiguous,
        // see http://stackoverflow.com/a/35008842/266378 for more discussion
        const auto is_contiguous = std::accumulate(
                                       first, last, std::pair<bool, int>(true, 0),
                                       [&first](std::pair<bool, int> res, decltype(*first) val)
        {
            res.first &= (val == *(std::next(std::addressof(*first), res.second++)));
            return res;
        }).first;
        assert(is_contiguous);
#endif

        // assertion to check that each element is 1 byte long
        static_assert(
            sizeof(typename iterator_traits<IteratorType>::value_type) == 1,
            "each element in the iterator range must have the size of 1 byte");

        const auto len = static_cast<size_t>(std::distance(first, last));
        if (JSON_LIKELY(len > 0))
        {
            // there is at least one element: use the address of first
            ia = std::make_shared<input_buffer_adapter>(reinterpret_cast<const char*>(&(*first)), len);
        }
        else
        {
            // the address of first cannot be used: use nullptr
            ia = std::make_shared<input_buffer_adapter>(nullptr, len);
        }
    }

    /// input adapter for array
    template<class T, std::size_t N>
    input_adapter(T (&array)[N])
        : input_adapter(std::begin(array), std::end(array)) {}

    /// input adapter for contiguous container
    template<class ContiguousContainer, typename
             std::enable_if<not std::is_pointer<ContiguousContainer>::value and
                            std::is_base_of<std::random_access_iterator_tag, typename iterator_traits<decltype(std::begin(std::declval<ContiguousContainer const>()))>::iterator_category>::value,
                            int>::type = 0>
    input_adapter(const ContiguousContainer& c)
        : input_adapter(std::begin(c), std::end(c)) {}

    operator input_adapter_t()
    {
        return ia;
    }

  private:
    /// the actual adapter
    input_adapter_t ia = nullptr;
};
}  // namespace detail
}  // namespace nlohmann

// #include <nlohmann/detail/input/json_sax.hpp>


#include <cassert> // assert
#include <cstddef>
#include <string> // string
#include <utility> // move
#include <vector> // vector

// #include <nlohmann/detail/exceptions.hpp>

// #include <nlohmann/detail/macro_scope.hpp>


namespace nlohmann
{

/*!
@brief SAX interface

This class describes the SAX interface used by @ref nlohmann::json::sax_parse.
Each function is called in different situations while the input is parsed. The
boolean return value informs the parser whether to continue processing the
input.
*/
template<typename BasicJsonType>
struct json_sax
{
    /// type for (signed) integers
    using number_integer_t = typename BasicJsonType::number_integer_t;
    /// type for unsigned integers
    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
    /// type for floating-point numbers
    using number_float_t = typename BasicJsonType::number_float_t;
    /// type for strings
    using string_t = typename BasicJsonType::string_t;

    /*!
    @brief a null value was read
    @return whether parsing should proceed
    */
    virtual bool null() = 0;

    /*!
    @brief a boolean value was read
    @param[in] val  boolean value
    @return whether parsing should proceed
    */
    virtual bool boolean(bool val) = 0;

    /*!
    @brief an integer number was read
    @param[in] val  integer value
    @return whether parsing should proceed
    */
    virtual bool number_integer(number_integer_t val) = 0;

    /*!
    @brief an unsigned integer number was read
    @param[in] val  unsigned integer value
    @return whether parsing should proceed
    */
    virtual bool number_unsigned(number_unsigned_t val) = 0;

    /*!
    @brief an floating-point number was read
    @param[in] val  floating-point value
    @param[in] s    raw token value
    @return whether parsing should proceed
    */
    virtual bool number_float(number_float_t val, const string_t& s) = 0;

    /*!
    @brief a string was read
    @param[in] val  string value
    @return whether parsing should proceed
    @note It is safe to move the passed string.
    */
    virtual bool string(string_t& val) = 0;

    /*!
    @brief the beginning of an object was read
    @param[in] elements  number of object elements or -1 if unknown
    @return whether parsing should proceed
    @note binary formats may report the number of elements
    */
    virtual bool start_object(std::size_t elements) = 0;

    /*!
    @brief an object key was read
    @param[in] val  object key
    @return whether parsing should proceed
    @note It is safe to move the passed string.
    */
    virtual bool key(string_t& val) = 0;

    /*!
    @brief the end of an object was read
    @return whether parsing should proceed
    */
    virtual bool end_object() = 0;

    /*!
    @brief the beginning of an array was read
    @param[in] elements  number of array elements or -1 if unknown
    @return whether parsing should proceed
    @note binary formats may report the number of elements
    */
    virtual bool start_array(std::size_t elements) = 0;

    /*!
    @brief the end of an array was read
    @return whether parsing should proceed
    */
    virtual bool end_array() = 0;

    /*!
    @brief a parse error occurred
    @param[in] position    the position in the input where the error occurs
    @param[in] last_token  the last read token
    @param[in] ex          an exception object describing the error
    @return whether parsing should proceed (must return false)
    */
    virtual bool parse_error(std::size_t position,
                             const std::string& last_token,
                             const detail::exception& ex) = 0;

    virtual ~json_sax() = default;
};


namespace detail
{
/*!
@brief SAX implementation to create a JSON value from SAX events

This class implements the @ref json_sax interface and processes the SAX events
to create a JSON value which makes it basically a DOM parser. The structure or
hierarchy of the JSON value is managed by the stack `ref_stack` which contains
a pointer to the respective array or object for each recursion depth.

After successful parsing, the value that is passed by reference to the
constructor contains the parsed value.

@tparam BasicJsonType  the JSON type
*/
template<typename BasicJsonType>
class json_sax_dom_parser
{
  public:
    using number_integer_t = typename BasicJsonType::number_integer_t;
    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
    using number_float_t = typename BasicJsonType::number_float_t;
    using string_t = typename BasicJsonType::string_t;

    /*!
    @param[in, out] r  reference to a JSON value that is manipulated while
                       parsing
    @param[in] allow_exceptions_  whether parse errors yield exceptions
    */
    explicit json_sax_dom_parser(BasicJsonType& r, const bool allow_exceptions_ = true)
        : root(r), allow_exceptions(allow_exceptions_)
    {}

    // make class move-only
    json_sax_dom_parser(const json_sax_dom_parser&) = delete;
    json_sax_dom_parser(json_sax_dom_parser&&) = default;
    json_sax_dom_parser& operator=(const json_sax_dom_parser&) = delete;
    json_sax_dom_parser& operator=(json_sax_dom_parser&&) = default;
    ~json_sax_dom_parser() = default;

    bool null()
    {
        handle_value(nullptr);
        return true;
    }

    bool boolean(bool val)
    {
        handle_value(val);
        return true;
    }

    bool number_integer(number_integer_t val)
    {
        handle_value(val);
        return true;
    }

    bool number_unsigned(number_unsigned_t val)
    {
        handle_value(val);
        return true;
    }

    bool number_float(number_float_t val, const string_t& /*unused*/)
    {
        handle_value(val);
        return true;
    }

    bool string(string_t& val)
    {
        handle_value(val);
        return true;
    }

    bool start_object(std::size_t len)
    {
        ref_stack.push_back(handle_value(BasicJsonType::value_t::object));

        if (JSON_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
        {
            JSON_THROW(out_of_range::create(408,
                                            "excessive object size: " + std::to_string(len)));
        }

        return true;
    }

    bool key(string_t& val)
    {
        // add null at given key and store the reference for later
        object_element = &(ref_stack.back()->m_value.object->operator[](val));
        return true;
    }

    bool end_object()
    {
        ref_stack.pop_back();
        return true;
    }

    bool start_array(std::size_t len)
    {
        ref_stack.push_back(handle_value(BasicJsonType::value_t::array));

        if (JSON_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
        {
            JSON_THROW(out_of_range::create(408,
                                            "excessive array size: " + std::to_string(len)));
        }

        return true;
    }

    bool end_array()
    {
        ref_stack.pop_back();
        return true;
    }

    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/,
                     const detail::exception& ex)
    {
        errored = true;
        if (allow_exceptions)
        {
            // determine the proper exception type from the id
            switch ((ex.id / 100) % 100)
            {
                case 1:
                    JSON_THROW(*static_cast<const detail::parse_error*>(&ex));
                case 4:
                    JSON_THROW(*static_cast<const detail::out_of_range*>(&ex));
                // LCOV_EXCL_START
                case 2:
                    JSON_THROW(*static_cast<const detail::invalid_iterator*>(&ex));
                case 3:
                    JSON_THROW(*static_cast<const detail::type_error*>(&ex));
                case 5:
                    JSON_THROW(*static_cast<const detail::other_error*>(&ex));
                default:
                    assert(false);
                    // LCOV_EXCL_STOP
            }
        }
        return false;
    }

    constexpr bool is_errored() const
    {
        return errored;
    }

  private:
    /*!
    @invariant If the ref stack is empty, then the passed value will be the new
               root.
    @invariant If the ref stack contains a value, then it is an array or an
               object to which we can add elements
    */
    template<typename Value>
    BasicJsonType* handle_value(Value&& v)
    {
        if (ref_stack.empty())
        {
            root = BasicJsonType(std::forward<Value>(v));
            return &root;
        }

        assert(ref_stack.back()->is_array() or ref_stack.back()->is_object());

        if (ref_stack.back()->is_array())
        {
            ref_stack.back()->m_value.array->emplace_back(std::forward<Value>(v));
            return &(ref_stack.back()->m_value.array->back());
        }

        assert(ref_stack.back()->is_object());
        assert(object_element);
        *object_element = BasicJsonType(std::forward<Value>(v));
        return object_element;
    }

    /// the parsed JSON value
    BasicJsonType& root;
    /// stack to model hierarchy of values
    std::vector<BasicJsonType*> ref_stack {};
    /// helper to hold the reference for the next object element
    BasicJsonType* object_element = nullptr;
    /// whether a syntax error occurred
    bool errored = false;
    /// whether to throw exceptions in case of errors
    const bool allow_exceptions = true;
};

template<typename BasicJsonType>
class json_sax_dom_callback_parser
{
  public:
    using number_integer_t = typename BasicJsonType::number_integer_t;
    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
    using number_float_t = typename BasicJsonType::number_float_t;
    using string_t = typename BasicJsonType::string_t;
    using parser_callback_t = typename BasicJsonType::parser_callback_t;
    using parse_event_t = typename BasicJsonType::parse_event_t;

    json_sax_dom_callback_parser(BasicJsonType& r,
                                 const parser_callback_t cb,
                                 const bool allow_exceptions_ = true)
        : root(r), callback(cb), allow_exceptions(allow_exceptions_)
    {
        keep_stack.push_back(true);
    }

    // make class move-only
    json_sax_dom_callback_parser(const json_sax_dom_callback_parser&) = delete;
    json_sax_dom_callback_parser(json_sax_dom_callback_parser&&) = default;
    json_sax_dom_callback_parser& operator=(const json_sax_dom_callback_parser&) = delete;
    json_sax_dom_callback_parser& operator=(json_sax_dom_callback_parser&&) = default;
    ~json_sax_dom_callback_parser() = default;

    bool null()
    {
        handle_value(nullptr);
        return true;
    }

    bool boolean(bool val)
    {
        handle_value(val);
        return true;
    }

    bool number_integer(number_integer_t val)
    {
        handle_value(val);
        return true;
    }

    bool number_unsigned(number_unsigned_t val)
    {
        handle_value(val);
        return true;
    }

    bool number_float(number_float_t val, const string_t& /*unused*/)
    {
        handle_value(val);
        return true;
    }

    bool string(string_t& val)
    {
        handle_value(val);
        return true;
    }

    bool start_object(std::size_t len)
    {
        // check callback for object start
        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::object_start, discarded);
        keep_stack.push_back(keep);

        auto val = handle_value(BasicJsonType::value_t::object, true);
        ref_stack.push_back(val.second);

        // check object limit
        if (ref_stack.back() and JSON_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
        {
            JSON_THROW(out_of_range::create(408, "excessive object size: " + std::to_string(len)));
        }

        return true;
    }

    bool key(string_t& val)
    {
        BasicJsonType k = BasicJsonType(val);

        // check callback for key
        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::key, k);
        key_keep_stack.push_back(keep);

        // add discarded value at given key and store the reference for later
        if (keep and ref_stack.back())
        {
            object_element = &(ref_stack.back()->m_value.object->operator[](val) = discarded);
        }

        return true;
    }

    bool end_object()
    {
        if (ref_stack.back() and not callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::object_end, *ref_stack.back()))
        {
            // discard object
            *ref_stack.back() = discarded;
        }

        assert(not ref_stack.empty());
        assert(not keep_stack.empty());
        ref_stack.pop_back();
        keep_stack.pop_back();

        if (not ref_stack.empty() and ref_stack.back() and ref_stack.back()->is_object())
        {
            // remove discarded value
            for (auto it = ref_stack.back()->begin(); it != ref_stack.back()->end(); ++it)
            {
                if (it->is_discarded())
                {
                    ref_stack.back()->erase(it);
                    break;
                }
            }
        }

        return true;
    }

    bool start_array(std::size_t len)
    {
        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::array_start, discarded);
        keep_stack.push_back(keep);

        auto val = handle_value(BasicJsonType::value_t::array, true);
        ref_stack.push_back(val.second);

        // check array limit
        if (ref_stack.back() and JSON_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
        {
            JSON_THROW(out_of_range::create(408, "excessive array size: " + std::to_string(len)));
        }

        return true;
    }

    bool end_array()
    {
        bool keep = true;

        if (ref_stack.back())
        {
            keep = callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::array_end, *ref_stack.back());
            if (not keep)
            {
                // discard array
                *ref_stack.back() = discarded;
            }
        }

        assert(not ref_stack.empty());
        assert(not keep_stack.empty());
        ref_stack.pop_back();
        keep_stack.pop_back();

        // remove discarded value
        if (not keep and not ref_stack.empty() and ref_stack.back()->is_array())
        {
            ref_stack.back()->m_value.array->pop_back();
        }

        return true;
    }

    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/,
                     const detail::exception& ex)
    {
        errored = true;
        if (allow_exceptions)
        {
            // determine the proper exception type from the id
            switch ((ex.id / 100) % 100)
            {
                case 1:
                    JSON_THROW(*static_cast<const detail::parse_error*>(&ex));
                case 4:
                    JSON_THROW(*static_cast<const detail::out_of_range*>(&ex));
                // LCOV_EXCL_START
                case 2:
                    JSON_THROW(*static_cast<const detail::invalid_iterator*>(&ex));
                case 3:
                    JSON_THROW(*static_cast<const detail::type_error*>(&ex));
                case 5:
                    JSON_THROW(*static_cast<const detail::other_error*>(&ex));
                default:
                    assert(false);
                    // LCOV_EXCL_STOP
            }
        }
        return false;
    }

    constexpr bool is_errored() const
    {
        return errored;
    }

  private:
    /*!
    @param[in] v  value to add to the JSON value we build during parsing
    @param[in] skip_callback  whether we should skip calling the callback
               function; this is required after start_array() and
               start_object() SAX events, because otherwise we would call the
               callback function with an empty array or object, respectively.

    @invariant If the ref stack is empty, then the passed value will be the new
               root.
    @invariant If the ref stack contains a value, then it is an array or an
               object to which we can add elements

    @return pair of boolean (whether value should be kept) and pointer (to the
            passed value in the ref_stack hierarchy; nullptr if not kept)
    */
    template<typename Value>
    std::pair<bool, BasicJsonType*> handle_value(Value&& v, const bool skip_callback = false)
    {
        assert(not keep_stack.empty());

        // do not handle this value if we know it would be added to a discarded
        // container
        if (not keep_stack.back())
        {
            return {false, nullptr};
        }

        // create value
        auto value = BasicJsonType(std::forward<Value>(v));

        // check callback
        const bool keep = skip_callback or callback(static_cast<int>(ref_stack.size()), parse_event_t::value, value);

        // do not handle this value if we just learnt it shall be discarded
        if (not keep)
        {
            return {false, nullptr};
        }

        if (ref_stack.empty())
        {
            root = std::move(value);
            return {true, &root};
        }

        // skip this value if we already decided to skip the parent
        // (https://github.com/nlohmann/json/issues/971#issuecomment-413678360)
        if (not ref_stack.back())
        {
            return {false, nullptr};
        }

        // we now only expect arrays and objects
        assert(ref_stack.back()->is_array() or ref_stack.back()->is_object());

        // array
        if (ref_stack.back()->is_array())
        {
            ref_stack.back()->m_value.array->push_back(std::move(value));
            return {true, &(ref_stack.back()->m_value.array->back())};
        }

        // object
        assert(ref_stack.back()->is_object());
        // check if we should store an element for the current key
        assert(not key_keep_stack.empty());
        const bool store_element = key_keep_stack.back();
        key_keep_stack.pop_back();

        if (not store_element)
        {
            return {false, nullptr};
        }

        assert(object_element);
        *object_element = std::move(value);
        return {true, object_element};
    }

    /// the parsed JSON value
    BasicJsonType& root;
    /// stack to model hierarchy of values
    std::vector<BasicJsonType*> ref_stack {};
    /// stack to manage which values to keep
    std::vector<bool> keep_stack {};
    /// stack to manage which object keys to keep
    std::vector<bool> key_keep_stack {};
    /// helper to hold the reference for the next object element
    BasicJsonType* object_element = nullptr;
    /// whether a syntax error occurred
    bool errored = false;
    /// callback function
    const parser_callback_t callback = nullptr;
    /// whether to throw exceptions in case of errors
    const bool allow_exceptions = true;
    /// a discarded value for the callback
    BasicJsonType discarded = BasicJsonType::value_t::discarded;
};

template<typename BasicJsonType>
class json_sax_acceptor
{
  public:
    using number_integer_t = typename BasicJsonType::number_integer_t;
    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
    using number_float_t = typename BasicJsonType::number_float_t;
    using string_t = typename BasicJsonType::string_t;

    bool null()
    {
        return true;
    }

    bool boolean(bool /*unused*/)
    {
        return true;
    }

    bool number_integer(number_integer_t /*unused*/)
    {
        return true;
    }

    bool number_unsigned(number_unsigned_t /*unused*/)
    {
        return true;
    }

    bool number_float(number_float_t /*unused*/, const string_t& /*unused*/)
    {
        return true;
    }

    bool string(string_t& /*unused*/)
    {
        return true;
    }

    bool start_object(std::size_t  /*unused*/ = std::size_t(-1))
    {
        return true;
    }

    bool key(string_t& /*unused*/)
    {
        return true;
    }

    bool end_object()
    {
        return true;
    }

    bool start_array(std::size_t  /*unused*/ = std::size_t(-1))
    {
        return true;
    }

    bool end_array()
    {
        return true;
    }

    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/, const detail::exception& /*unused*/)
    {
        return false;
    }
};
}  // namespace detail

}  // namespace nlohmann

// #include <nlohmann/detail/macro_scope.hpp>

// #include <nlohmann/detail/meta/is_sax.hpp>


#include <cstdint> // size_t
#include <utility> // declval
#include <string> // string

// #include <nlohmann/detail/meta/detected.hpp>

// #include <nlohmann/detail/meta/type_traits.hpp>


namespace nlohmann
{
namespace detail
{
template <typename T>
using null_function_t = decltype(std::declval<T&>().null());

template <typename T>
using boolean_function_t =
    decltype(std::declval<T&>().boolean(std::declval<bool>()));

template <typename T, typename Integer>
using number_integer_function_t =
    decltype(std::declval<T&>().number_integer(std::declval<Integer>()));

template <typename T, typename Unsigned>
using number_unsigned_function_t =
    decltype(std::declval<T&>().number_unsigned(std::declval<Unsigned>()));

template <typename T, typename Float, typename String>
using number_float_function_t = decltype(std::declval<T&>().number_float(
                                    std::declval<Float>(), std::declval<const String&>()));

template <typename T, typename String>
using string_function_t =
    decltype(std::declval<T&>().string(std::declval<String&>()));

template <typename T>
using start_object_function_t =
    decltype(std::declval<T&>().start_object(std::declval<std::size_t>()));

template <typename T, typename String>
using key_function_t =
    decltype(std::declval<T&>().key(std::declval<String&>()));

template <typename T>
using end_object_function_t = decltype(std::declval<T&>().end_object());

template <typename T>
using start_array_function_t =
    decltype(std::declval<T&>().start_array(std::declval<std::size_t>()));

template <typename T>
using end_array_function_t = decltype(std::declval<T&>().end_array());

template <typename T, typename Exception>
using parse_error_function_t = decltype(std::declval<T&>().parse_error(
        std::declval<std::size_t>(), std::declval<const std::string&>(),
        std::declval<const Exception&>()));

template <typename SAX, typename BasicJsonType>
struct is_sax
{
  private:
    static_assert(is_basic_json<BasicJsonType>::value,
                  "BasicJsonType must be of type basic_json<...>");

    using number_integer_t = typename BasicJsonType::number_integer_t;
    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
    using number_float_t = typename BasicJsonType::number_float_t;
    using string_t = typename BasicJsonType::string_t;
    using exception_t = typename BasicJsonType::exception;

  public:
    static constexpr bool value =
        is_detected_exact<bool, null_function_t, SAX>::value &&
        is_detected_exact<bool, boolean_function_t, SAX>::value &&
        is_detected_exact<bool, number_integer_function_t, SAX,
        number_integer_t>::value &&
        is_detected_exact<bool, number_unsigned_function_t, SAX,
        number_unsigned_t>::value &&
        is_detected_exact<bool, number_float_function_t, SAX, number_float_t,
        string_t>::value &&
        is_detected_exact<bool, string_function_t, SAX, string_t>::value &&
        is_detected_exact<bool, start_object_function_t, SAX>::value &&
        is_detected_exact<bool, key_function_t, SAX, string_t>::value &&
        is_detected_exact<bool, end_object_function_t, SAX>::value &&
        is_detected_exact<bool, start_array_function_t, SAX>::value &&
        is_detected_exact<bool, end_array_function_t, SAX>::value &&
        is_detected_exact<bool, parse_error_function_t, SAX, exception_t>::value;
};

template <typename SAX, typename BasicJsonType>
struct is_sax_static_asserts
{
  private:
    static_assert(is_basic_json<BasicJsonType>::value,
                  "BasicJsonType must be of type basic_json<...>");

    using number_integer_t = typename BasicJsonType::number_integer_t;
    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
    using number_float_t = typename BasicJsonType::number_float_t;
    using string_t = typename BasicJsonType::string_t;
    using exception_t = typename BasicJsonType::exception;

  public:
    static_assert(is_detected_exact<bool, null_function_t, SAX>::value,
                  "Missing/invalid function: bool null()");
    static_assert(is_detected_exact<bool, boolean_function_t, SAX>::value,
                  "Missing/invalid function: bool boolean(bool)");
    static_assert(is_detected_exact<bool, boolean_function_t, SAX>::value,
                  "Missing/invalid function: bool boolean(bool)");
    static_assert(
        is_detected_exact<bool, number_integer_function_t, SAX,
        number_integer_t>::value,
        "Missing/invalid function: bool number_integer(number_integer_t)");
    static_assert(
        is_detected_exact<bool, number_unsigned_function_t, SAX,
        number_unsigned_t>::value,
        "Missing/invalid function: bool number_unsigned(number_unsigned_t)");
    static_assert(is_detected_exact<bool, number_float_function_t, SAX,
                  number_float_t, string_t>::value,
                  "Missing/invalid function: bool number_float(number_float_t, const string_t&)");
    static_assert(
        is_detected_exact<bool, string_function_t, SAX, string_t>::value,
        "Missing/invalid function: bool string(string_t&)");
    static_assert(is_detected_exact<bool, start_object_function_t, SAX>::value,
                  "Missing/invalid function: bool start_object(std::size_t)");
    static_assert(is_detected_exact<bool, key_function_t, SAX, string_t>::value,
                  "Missing/invalid function: bool key(string_t&)");
    static_assert(is_detected_exact<bool, end_object_function_t, SAX>::value,
                  "Missing/invalid function: bool end_object()");
    static_assert(is_detected_exact<bool, start_array_function_t, SAX>::value,
                  "Missing/invalid function: bool start_array(std::size_t)");
    static_assert(is_detected_exact<bool, end_array_function_t, SAX>::value,
                  "Missing/invalid function: bool end_array()");
    static_assert(
        is_detected_exact<bool, parse_error_function_t, SAX, exception_t>::value,
        "Missing/invalid function: bool parse_error(std::size_t, const "
        "std::string&, const exception&)");
};
}  // namespace detail
}  // namespace nlohmann

// #include <nlohmann/detail/value_t.hpp>


namespace nlohmann
{
namespace detail
{
///////////////////
// binary reader //
///////////////////

/*!
@brief deserialization of CBOR, MessagePack, and UBJSON values
*/
template<typename BasicJsonType, typename SAX = json_sax_dom_parser<BasicJsonType>>
class binary_reader
{
    using number_integer_t = typename BasicJsonType::number_integer_t;
    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
    using number_float_t = typename BasicJsonType::number_float_t;
    using string_t = typename BasicJsonType::string_t;
    using json_sax_t = SAX;

  public:
    /*!
    @brief create a binary reader

    @param[in] adapter  input adapter to read from
    */
    explicit binary_reader(input_adapter_t adapter) : ia(std::move(adapter))
    {
        (void)detail::is_sax_static_asserts<SAX, BasicJsonType> {};
        assert(ia);
    }

    // make class move-only
    binary_reader(const binary_reader&) = delete;
    binary_reader(binary_reader&&) = default;
    binary_reader& operator=(const binary_reader&) = delete;
    binary_reader& operator=(binary_reader&&) = default;
    ~binary_reader() = default;

    /*!
    @param[in] format  the binary format to parse
    @param[in] sax_    a SAX event processor
    @param[in] strict  whether to expect the input to be consumed completed

    @return
    */
    bool sax_parse(const input_format_t format,
                   json_sax_t* sax_,
                   const bool strict = true)
    {
        sax = sax_;
        bool result = false;

        switch (format)
        {
            case input_format_t::bson:
                result = parse_bson_internal();
                break;

            case input_format_t::cbor:
                result = parse_cbor_internal();
                break;

            case input_format_t::msgpack:
                result = parse_msgpack_internal();
                break;

            case input_format_t::ubjson:
                result = parse_ubjson_internal();
                break;

            default:            // LCOV_EXCL_LINE
                assert(false);  // LCOV_EXCL_LINE
        }

        // strict mode: next byte must be EOF
        if (result and strict)
        {
            if (format == input_format_t::ubjson)
            {
                get_ignore_noop();
            }
            else
            {
                get();
            }

            if (JSON_UNLIKELY(current != std::char_traits<char>::eof()))
            {
                return sax->parse_error(chars_read, get_token_string(),
                                        parse_error::create(110, chars_read, exception_message(format, "expected end of input; last byte: 0x" + get_token_string(), "value")));
            }
        }

        return result;
    }

    /*!
    @brief determine system byte order

    @return true if and only if system's byte order is little endian

    @note from http://stackoverflow.com/a/1001328/266378
    */
    static constexpr bool little_endianess(int num = 1) noexcept
    {
        return *reinterpret_cast<char*>(&num) == 1;
    }

  private:
    //////////
    // BSON //
    //////////

    /*!
    @brief Reads in a BSON-object and passes it to the SAX-parser.
    @return whether a valid BSON-value was passed to the SAX parser
    */
    bool parse_bson_internal()
    {
        std::int32_t document_size;
        get_number<std::int32_t, true>(input_format_t::bson, document_size);

        if (JSON_UNLIKELY(not sax->start_object(std::size_t(-1))))
        {
            return false;
        }

        if (JSON_UNLIKELY(not parse_bson_element_list(/*is_array*/false)))
        {
            return false;
        }

        return sax->end_object();
    }

    /*!
    @brief Parses a C-style string from the BSON input.
    @param[in, out] result  A reference to the string variable where the read
                            string is to be stored.
    @return `true` if the \x00-byte indicating the end of the string was
             encountered before the EOF; false` indicates an unexpected EOF.
    */
    bool get_bson_cstr(string_t& result)
    {
        auto out = std::back_inserter(result);
        while (true)
        {
            get();
            if (JSON_UNLIKELY(not unexpect_eof(input_format_t::bson, "cstring")))
            {
                return false;
            }
            if (current == 0x00)
            {
                return true;
            }
            *out++ = static_cast<char>(current);
        }

        return true;
    }

    /*!
    @brief Parses a zero-terminated string of length @a len from the BSON
           input.
    @param[in] len  The length (including the zero-byte at the end) of the
                    string to be read.
    @param[in, out] result  A reference to the string variable where the read
                            string is to be stored.
    @tparam NumberType The type of the length @a len
    @pre len >= 1
    @return `true` if the string was successfully parsed
    */
    template<typename NumberType>
    bool get_bson_string(const NumberType len, string_t& result)
    {
        if (JSON_UNLIKELY(len < 1))
        {
            auto last_token = get_token_string();
            return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::bson, "string length must be at least 1, is " + std::to_string(len), "string")));
        }

        return get_string(input_format_t::bson, len - static_cast<NumberType>(1), result) and get() != std::char_traits<char>::eof();
    }

    /*!
    @brief Read a BSON document element of the given @a element_type.
    @param[in] element_type The BSON element type, c.f. http://bsonspec.org/spec.html
    @param[in] element_type_parse_position The position in the input stream,
               where the `element_type` was read.
    @warning Not all BSON element types are supported yet. An unsupported
             @a element_type will give rise to a parse_error.114:
             Unsupported BSON record type 0x...
    @return whether a valid BSON-object/array was passed to the SAX parser
    */
    bool parse_bson_element_internal(const int element_type,
                                     const std::size_t element_type_parse_position)
    {
        switch (element_type)
        {
            case 0x01: // double
            {
                double number;
                return get_number<double, true>(input_format_t::bson, number) and sax->number_float(static_cast<number_float_t>(number), "");
            }

            case 0x02: // string
            {
                std::int32_t len;
                string_t value;
                return get_number<std::int32_t, true>(input_format_t::bson, len) and get_bson_string(len, value) and sax->string(value);
            }

            case 0x03: // object
            {
                return parse_bson_internal();
            }

            case 0x04: // array
            {
                return parse_bson_array();
            }

            case 0x08: // boolean
            {
                return sax->boolean(get() != 0);
            }

            case 0x0A: // null
            {
                return sax->null();
            }

            case 0x10: // int32
            {
                std::int32_t value;
                return get_number<std::int32_t, true>(input_format_t::bson, value) and sax->number_integer(value);
            }

            case 0x12: // int64
            {
                std::int64_t value;
                return get_number<std::int64_t, true>(input_format_t::bson, value) and sax->number_integer(value);
            }

            default: // anything else not supported (yet)
            {
                std::array<char, 3> cr{{}};
                (std::snprintf)(cr.data(), cr.size(), "%.2hhX", static_cast<unsigned char>(element_type));
                return sax->parse_error(element_type_parse_position, std::string(cr.data()), parse_error::create(114, element_type_parse_position, "Unsupported BSON record type 0x" + std::string(cr.data())));
            }
        }
    }

    /*!
    @brief Read a BSON element list (as specified in the BSON-spec)

    The same binary layout is used for objects and arrays, hence it must be
    indicated with the argument @a is_array which one is expected
    (true --> array, false --> object).

    @param[in] is_array Determines if the element list being read is to be
                        treated as an object (@a is_array == false), or as an
                        array (@a is_array == true).
    @return whether a valid BSON-object/array was passed to the SAX parser
    */
    bool parse_bson_element_list(const bool is_array)
    {
        string_t key;
        while (int element_type = get())
        {
            if (JSON_UNLIKELY(not unexpect_eof(input_format_t::bson, "element list")))
            {
                return false;
            }

            const std::size_t element_type_parse_position = chars_read;
            if (JSON_UNLIKELY(not get_bson_cstr(key)))
            {
                return false;
            }

            if (not is_array and not sax->key(key))
            {
                return false;
            }

            if (JSON_UNLIKELY(not parse_bson_element_internal(element_type, element_type_parse_position)))
            {
                return false;
            }

            // get_bson_cstr only appends
            key.clear();
        }

        return true;
    }

    /*!
    @brief Reads an array from the BSON input and passes it to the SAX-parser.
    @return whether a valid BSON-array was passed to the SAX parser
    */
    bool parse_bson_array()
    {
        std::int32_t document_size;
        get_number<std::int32_t, true>(input_format_t::bson, document_size);

        if (JSON_UNLIKELY(not sax->start_array(std::size_t(-1))))
        {
            return false;
        }

        if (JSON_UNLIKELY(not parse_bson_element_list(/*is_array*/true)))
        {
            return false;
        }

        return sax->end_array();
    }

    //////////
    // CBOR //
    //////////

    /*!
    @param[in] get_char  whether a new character should be retrieved from the
                         input (true, default) or whether the last read
                         character should be considered instead

    @return whether a valid CBOR value was passed to the SAX parser
    */
    bool parse_cbor_internal(const bool get_char = true)
    {
        switch (get_char ? get() : current)
        {
            // EOF
            case std::char_traits<char>::eof():
                return unexpect_eof(input_format_t::cbor, "value");

            // 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 sax->number_unsigned(static_cast<number_unsigned_t>(current));

            case 0x18: // Unsigned integer (one-byte uint8_t follows)
            {
                std::uint8_t number;
                return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
            }

            case 0x19: // Unsigned integer (two-byte uint16_t follows)
            {
                std::uint16_t number;
                return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
            }

            case 0x1A: // Unsigned integer (four-byte uint32_t follows)
            {
                std::uint32_t number;
                return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
            }

            case 0x1B: // Unsigned integer (eight-byte uint64_t follows)
            {
                std::uint64_t number;
                return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
            }

            // Negative integer -1-0x00..-1-0x17 (-1..-24)
            case 0x20:
            case 0x21:
            case 0x22:
            case 0x23:
            case 0x24:
            case 0x25:
            case 0x26:
            case 0x27:
            case 0x28:
            case 0x29:
            case 0x2A:
            case 0x2B:
            case 0x2C:
            case 0x2D:
            case 0x2E:
            case 0x2F:
            case 0x30:
            case 0x31:
            case 0x32:
            case 0x33:
            case 0x34:
            case 0x35:
            case 0x36:
            case 0x37:
                return sax->number_integer(static_cast<std::int8_t>(0x20 - 1 - current));

            case 0x38: // Negative integer (one-byte uint8_t follows)
            {
                std::uint8_t number;
                return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
            }

            case 0x39: // Negative integer -1-n (two-byte uint16_t follows)
            {
                std::uint16_t number;
                return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
            }

            case 0x3A: // Negative integer -1-n (four-byte uint32_t follows)
            {
                std::uint32_t number;
                return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
            }

            case 0x3B: // Negative integer -1-n (eight-byte uint64_t follows)
            {
                std::uint64_t number;
                return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1)
                        - static_cast<number_integer_t>(number));
            }

            // UTF-8 string (0x00..0x17 bytes follow)
            case 0x60:
            case 0x61:
            case 0x62:
            case 0x63:
            case 0x64:
            case 0x65:
            case 0x66:
            case 0x67:
            case 0x68:
            case 0x69:
            case 0x6A:
            case 0x6B:
            case 0x6C:
            case 0x6D:
            case 0x6E:
            case 0x6F:
            case 0x70:
            case 0x71:
            case 0x72:
            case 0x73:
            case 0x74:
            case 0x75:
            case 0x76:
            case 0x77:
            case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
            case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
            case 0x7A: // UTF-8 string (four-byte uint32_t for n follow)
            case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow)
            case 0x7F: // UTF-8 string (indefinite length)
            {
                string_t s;
                return get_cbor_string(s) and sax->string(s);
            }

            // 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:
                return get_cbor_array(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x1Fu));

            case 0x98: // array (one-byte uint8_t for n follows)
            {
                std::uint8_t len;
                return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
            }

            case 0x99: // array (two-byte uint16_t for n follow)
            {
                std::uint16_t len;
                return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
            }

            case 0x9A: // array (four-byte uint32_t for n follow)
            {
                std::uint32_t len;
                return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
            }

            case 0x9B: // array (eight-byte uint64_t for n follow)
            {
                std::uint64_t len;
                return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
            }

            case 0x9F: // array (indefinite length)
                return get_cbor_array(std::size_t(-1));

            // 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:
                return get_cbor_object(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x1Fu));

            case 0xB8: // map (one-byte uint8_t for n follows)
            {
                std::uint8_t len;
                return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
            }

            case 0xB9: // map (two-byte uint16_t for n follow)
            {
                std::uint16_t len;
                return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
            }

            case 0xBA: // map (four-byte uint32_t for n follow)
            {
                std::uint32_t len;
                return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
            }

            case 0xBB: // map (eight-byte uint64_t for n follow)
            {
                std::uint64_t len;
                return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
            }

            case 0xBF: // map (indefinite length)
                return get_cbor_object(std::size_t(-1));

            case 0xF4: // false
                return sax->boolean(false);

            case 0xF5: // true
                return sax->boolean(true);

            case 0xF6: // null
                return sax->null();

            case 0xF9: // Half-Precision Float (two-byte IEEE 754)
            {
                const int byte1_raw = get();
                if (JSON_UNLIKELY(not unexpect_eof(input_format_t::cbor, "number")))
                {
                    return false;
                }
                const int byte2_raw = get();
                if (JSON_UNLIKELY(not unexpect_eof(input_format_t::cbor, "number")))
                {
                    return false;
                }

                const auto byte1 = static_cast<unsigned char>(byte1_raw);
                const auto byte2 = static_cast<unsigned char>(byte2_raw);

                // 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 auto half = static_cast<unsigned int>((byte1 << 8u) + byte2);
                const double val = [&half]
                {
                    const int exp = (half >> 10u) & 0x1Fu;
                    const unsigned int mant = half & 0x3FFu;
                    assert(0 <= exp and exp <= 32);
                    assert(0 <= mant and mant <= 1024);
                    switch (exp)
                    {
                        case 0:
                            return std::ldexp(mant, -24);
                        case 31:
                            return (mant == 0)
                            ? std::numeric_limits<double>::infinity()
                            : std::numeric_limits<double>::quiet_NaN();
                        default:
                            return std::ldexp(mant + 1024, exp - 25);
                    }
                }();
                return sax->number_float((half & 0x8000u) != 0
                                         ? static_cast<number_float_t>(-val)
                                         : static_cast<number_float_t>(val), "");
            }

            case 0xFA: // Single-Precision Float (four-byte IEEE 754)
            {
                float number;
                return get_number(input_format_t::cbor, number) and sax->number_float(static_cast<number_float_t>(number), "");
            }

            case 0xFB: // Double-Precision Float (eight-byte IEEE 754)
            {
                double number;
                return get_number(input_format_t::cbor, number) and sax->number_float(static_cast<number_float_t>(number), "");
            }

            default: // anything else (0xFF is handled inside the other types)
            {
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::cbor, "invalid byte: 0x" + last_token, "value")));
            }
        }
    }

    /*!
    @brief reads a CBOR string

    This function first reads starting bytes to determine the expected
    string length and then copies this number of bytes into a string.
    Additionally, CBOR's strings with indefinite lengths are supported.

    @param[out] result  created string

    @return whether string creation completed
    */
    bool get_cbor_string(string_t& result)
    {
        if (JSON_UNLIKELY(not unexpect_eof(input_format_t::cbor, "string")))
        {
            return false;
        }

        switch (current)
        {
            // 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:
            {
                return get_string(input_format_t::cbor, static_cast<unsigned int>(current) & 0x1Fu, result);
            }

            case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
            {
                std::uint8_t len;
                return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
            }

            case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
            {
                std::uint16_t len;
                return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
            }

            case 0x7A: // UTF-8 string (four-byte uint32_t for n follow)
            {
                std::uint32_t len;
                return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
            }

            case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow)
            {
                std::uint64_t len;
                return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
            }

            case 0x7F: // UTF-8 string (indefinite length)
            {
                while (get() != 0xFF)
                {
                    string_t chunk;
                    if (not get_cbor_string(chunk))
                    {
                        return false;
                    }
                    result.append(chunk);
                }
                return true;
            }

            default:
            {
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::cbor, "expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x" + last_token, "string")));
            }
        }
    }

    /*!
    @param[in] len  the length of the array or std::size_t(-1) for an
                    array of indefinite size
    @return whether array creation completed
    */
    bool get_cbor_array(const std::size_t len)
    {
        if (JSON_UNLIKELY(not sax->start_array(len)))
        {
            return false;
        }

        if (len != std::size_t(-1))
        {
            for (std::size_t i = 0; i < len; ++i)
            {
                if (JSON_UNLIKELY(not parse_cbor_internal()))
                {
                    return false;
                }
            }
        }
        else
        {
            while (get() != 0xFF)
            {
                if (JSON_UNLIKELY(not parse_cbor_internal(false)))
                {
                    return false;
                }
            }
        }

        return sax->end_array();
    }

    /*!
    @param[in] len  the length of the object or std::size_t(-1) for an
                    object of indefinite size
    @return whether object creation completed
    */
    bool get_cbor_object(const std::size_t len)
    {
        if (JSON_UNLIKELY(not sax->start_object(len)))
        {
            return false;
        }

        string_t key;
        if (len != std::size_t(-1))
        {
            for (std::size_t i = 0; i < len; ++i)
            {
                get();
                if (JSON_UNLIKELY(not get_cbor_string(key) or not sax->key(key)))
                {
                    return false;
                }

                if (JSON_UNLIKELY(not parse_cbor_internal()))
                {
                    return false;
                }
                key.clear();
            }
        }
        else
        {
            while (get() != 0xFF)
            {
                if (JSON_UNLIKELY(not get_cbor_string(key) or not sax->key(key)))
                {
                    return false;
                }

                if (JSON_UNLIKELY(not parse_cbor_internal()))
                {
                    return false;
                }
                key.clear();
            }
        }

        return sax->end_object();
    }

    /////////////
    // MsgPack //
    /////////////

    /*!
    @return whether a valid MessagePack value was passed to the SAX parser
    */
    bool parse_msgpack_internal()
    {
        switch (get())
        {
            // EOF
            case std::char_traits<char>::eof():
                return unexpect_eof(input_format_t::msgpack, "value");

            // positive fixint
            case 0x00:
            case 0x01:
            case 0x02:
            case 0x03:
            case 0x04:
            case 0x05:
            case 0x06:
            case 0x07:
            case 0x08:
            case 0x09:
            case 0x0A:
            case 0x0B:
            case 0x0C:
            case 0x0D:
            case 0x0E:
            case 0x0F:
            case 0x10:
            case 0x11:
            case 0x12:
            case 0x13:
            case 0x14:
            case 0x15:
            case 0x16:
            case 0x17:
            case 0x18:
            case 0x19:
            case 0x1A:
            case 0x1B:
            case 0x1C:
            case 0x1D:
            case 0x1E:
            case 0x1F:
            case 0x20:
            case 0x21:
            case 0x22:
            case 0x23:
            case 0x24:
            case 0x25:
            case 0x26:
            case 0x27:
            case 0x28:
            case 0x29:
            case 0x2A:
            case 0x2B:
            case 0x2C:
            case 0x2D:
            case 0x2E:
            case 0x2F:
            case 0x30:
            case 0x31:
            case 0x32:
            case 0x33:
            case 0x34:
            case 0x35:
            case 0x36:
            case 0x37:
            case 0x38:
            case 0x39:
            case 0x3A:
            case 0x3B:
            case 0x3C:
            case 0x3D:
            case 0x3E:
            case 0x3F:
            case 0x40:
            case 0x41:
            case 0x42:
            case 0x43:
            case 0x44:
            case 0x45:
            case 0x46:
            case 0x47:
            case 0x48:
            case 0x49:
            case 0x4A:
            case 0x4B:
            case 0x4C:
            case 0x4D:
            case 0x4E:
            case 0x4F:
            case 0x50:
            case 0x51:
            case 0x52:
            case 0x53:
            case 0x54:
            case 0x55:
            case 0x56:
            case 0x57:
            case 0x58:
            case 0x59:
            case 0x5A:
            case 0x5B:
            case 0x5C:
            case 0x5D:
            case 0x5E:
            case 0x5F:
            case 0x60:
            case 0x61:
            case 0x62:
            case 0x63:
            case 0x64:
            case 0x65:
            case 0x66:
            case 0x67:
            case 0x68:
            case 0x69:
            case 0x6A:
            case 0x6B:
            case 0x6C:
            case 0x6D:
            case 0x6E:
            case 0x6F:
            case 0x70:
            case 0x71:
            case 0x72:
            case 0x73:
            case 0x74:
            case 0x75:
            case 0x76:
            case 0x77:
            case 0x78:
            case 0x79:
            case 0x7A:
            case 0x7B:
            case 0x7C:
            case 0x7D:
            case 0x7E:
            case 0x7F:
                return sax->number_unsigned(static_cast<number_unsigned_t>(current));

            // fixmap
            case 0x80:
            case 0x81:
            case 0x82:
            case 0x83:
            case 0x84:
            case 0x85:
            case 0x86:
            case 0x87:
            case 0x88:
            case 0x89:
            case 0x8A:
            case 0x8B:
            case 0x8C:
            case 0x8D:
            case 0x8E:
            case 0x8F:
                return get_msgpack_object(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x0Fu));

            // fixarray
            case 0x90:
            case 0x91:
            case 0x92:
            case 0x93:
            case 0x94:
            case 0x95:
            case 0x96:
            case 0x97:
            case 0x98:
            case 0x99:
            case 0x9A:
            case 0x9B:
            case 0x9C:
            case 0x9D:
            case 0x9E:
            case 0x9F:
                return get_msgpack_array(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x0Fu));

            // fixstr
            case 0xA0:
            case 0xA1:
            case 0xA2:
            case 0xA3:
            case 0xA4:
            case 0xA5:
            case 0xA6:
            case 0xA7:
            case 0xA8:
            case 0xA9:
            case 0xAA:
            case 0xAB:
            case 0xAC:
            case 0xAD:
            case 0xAE:
            case 0xAF:
            case 0xB0:
            case 0xB1:
            case 0xB2:
            case 0xB3:
            case 0xB4:
            case 0xB5:
            case 0xB6:
            case 0xB7:
            case 0xB8:
            case 0xB9:
            case 0xBA:
            case 0xBB:
            case 0xBC:
            case 0xBD:
            case 0xBE:
            case 0xBF:
            {
                string_t s;
                return get_msgpack_string(s) and sax->string(s);
            }

            case 0xC0: // nil
                return sax->null();

            case 0xC2: // false
                return sax->boolean(false);

            case 0xC3: // true
                return sax->boolean(true);

            case 0xCA: // float 32
            {
                float number;
                return get_number(input_format_t::msgpack, number) and sax->number_float(static_cast<number_float_t>(number), "");
            }

            case 0xCB: // float 64
            {
                double number;
                return get_number(input_format_t::msgpack, number) and sax->number_float(static_cast<number_float_t>(number), "");
            }

            case 0xCC: // uint 8
            {
                std::uint8_t number;
                return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
            }

            case 0xCD: // uint 16
            {
                std::uint16_t number;
                return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
            }

            case 0xCE: // uint 32
            {
                std::uint32_t number;
                return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
            }

            case 0xCF: // uint 64
            {
                std::uint64_t number;
                return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
            }

            case 0xD0: // int 8
            {
                std::int8_t number;
                return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
            }

            case 0xD1: // int 16
            {
                std::int16_t number;
                return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
            }

            case 0xD2: // int 32
            {
                std::int32_t number;
                return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
            }

            case 0xD3: // int 64
            {
                std::int64_t number;
                return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
            }

            case 0xD9: // str 8
            case 0xDA: // str 16
            case 0xDB: // str 32
            {
                string_t s;
                return get_msgpack_string(s) and sax->string(s);
            }

            case 0xDC: // array 16
            {
                std::uint16_t len;
                return get_number(input_format_t::msgpack, len) and get_msgpack_array(static_cast<std::size_t>(len));
            }

            case 0xDD: // array 32
            {
                std::uint32_t len;
                return get_number(input_format_t::msgpack, len) and get_msgpack_array(static_cast<std::size_t>(len));
            }

            case 0xDE: // map 16
            {
                std::uint16_t len;
                return get_number(input_format_t::msgpack, len) and get_msgpack_object(static_cast<std::size_t>(len));
            }

            case 0xDF: // map 32
            {
                std::uint32_t len;
                return get_number(input_format_t::msgpack, len) and get_msgpack_object(static_cast<std::size_t>(len));
            }

            // negative fixint
            case 0xE0:
            case 0xE1:
            case 0xE2:
            case 0xE3:
            case 0xE4:
            case 0xE5:
            case 0xE6:
            case 0xE7:
            case 0xE8:
            case 0xE9:
            case 0xEA:
            case 0xEB:
            case 0xEC:
            case 0xED:
            case 0xEE:
            case 0xEF:
            case 0xF0:
            case 0xF1:
            case 0xF2:
            case 0xF3:
            case 0xF4:
            case 0xF5:
            case 0xF6:
            case 0xF7:
            case 0xF8:
            case 0xF9:
            case 0xFA:
            case 0xFB:
            case 0xFC:
            case 0xFD:
            case 0xFE:
            case 0xFF:
                return sax->number_integer(static_cast<std::int8_t>(current));

            default: // anything else
            {
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::msgpack, "invalid byte: 0x" + last_token, "value")));
            }
        }
    }

    /*!
    @brief reads a MessagePack string

    This function first reads starting bytes to determine the expected
    string length and then copies this number of bytes into a string.

    @param[out] result  created string

    @return whether string creation completed
    */
    bool get_msgpack_string(string_t& result)
    {
        if (JSON_UNLIKELY(not unexpect_eof(input_format_t::msgpack, "string")))
        {
            return false;
        }

        switch (current)
        {
            // fixstr
            case 0xA0:
            case 0xA1:
            case 0xA2:
            case 0xA3:
            case 0xA4:
            case 0xA5:
            case 0xA6:
            case 0xA7:
            case 0xA8:
            case 0xA9:
            case 0xAA:
            case 0xAB:
            case 0xAC:
            case 0xAD:
            case 0xAE:
            case 0xAF:
            case 0xB0:
            case 0xB1:
            case 0xB2:
            case 0xB3:
            case 0xB4:
            case 0xB5:
            case 0xB6:
            case 0xB7:
            case 0xB8:
            case 0xB9:
            case 0xBA:
            case 0xBB:
            case 0xBC:
            case 0xBD:
            case 0xBE:
            case 0xBF:
            {
                return get_string(input_format_t::msgpack, static_cast<unsigned int>(current) & 0x1Fu, result);
            }

            case 0xD9: // str 8
            {
                std::uint8_t len;
                return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
            }

            case 0xDA: // str 16
            {
                std::uint16_t len;
                return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
            }

            case 0xDB: // str 32
            {
                std::uint32_t len;
                return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
            }

            default:
            {
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::msgpack, "expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0x" + last_token, "string")));
            }
        }
    }

    /*!
    @param[in] len  the length of the array
    @return whether array creation completed
    */
    bool get_msgpack_array(const std::size_t len)
    {
        if (JSON_UNLIKELY(not sax->start_array(len)))
        {
            return false;
        }

        for (std::size_t i = 0; i < len; ++i)
        {
            if (JSON_UNLIKELY(not parse_msgpack_internal()))
            {
                return false;
            }
        }

        return sax->end_array();
    }

    /*!
    @param[in] len  the length of the object
    @return whether object creation completed
    */
    bool get_msgpack_object(const std::size_t len)
    {
        if (JSON_UNLIKELY(not sax->start_object(len)))
        {
            return false;
        }

        string_t key;
        for (std::size_t i = 0; i < len; ++i)
        {
            get();
            if (JSON_UNLIKELY(not get_msgpack_string(key) or not sax->key(key)))
            {
                return false;
            }

            if (JSON_UNLIKELY(not parse_msgpack_internal()))
            {
                return false;
            }
            key.clear();
        }

        return sax->end_object();
    }

    ////////////
    // UBJSON //
    ////////////

    /*!
    @param[in] get_char  whether a new character should be retrieved from the
                         input (true, default) or whether the last read
                         character should be considered instead

    @return whether a valid UBJSON value was passed to the SAX parser
    */
    bool parse_ubjson_internal(const bool get_char = true)
    {
        return get_ubjson_value(get_char ? get_ignore_noop() : current);
    }

    /*!
    @brief reads a UBJSON string

    This function is either called after reading the 'S' byte explicitly
    indicating a string, or in case of an object key where the 'S' byte can be
    left out.

    @param[out] result   created string
    @param[in] get_char  whether a new character should be retrieved from the
                         input (true, default) or whether the last read
                         character should be considered instead

    @return whether string creation completed
    */
    bool get_ubjson_string(string_t& result, const bool get_char = true)
    {
        if (get_char)
        {
            get();  // TODO(niels): may we ignore N here?
        }

        if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "value")))
        {
            return false;
        }

        switch (current)
        {
            case 'U':
            {
                std::uint8_t len;
                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
            }

            case 'i':
            {
                std::int8_t len;
                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
            }

            case 'I':
            {
                std::int16_t len;
                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
            }

            case 'l':
            {
                std::int32_t len;
                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
            }

            case 'L':
            {
                std::int64_t len;
                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
            }

            default:
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "expected length type specification (U, i, I, l, L); last byte: 0x" + last_token, "string")));
        }
    }

    /*!
    @param[out] result  determined size
    @return whether size determination completed
    */
    bool get_ubjson_size_value(std::size_t& result)
    {
        switch (get_ignore_noop())
        {
            case 'U':
            {
                std::uint8_t number;
                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
                {
                    return false;
                }
                result = static_cast<std::size_t>(number);
                return true;
            }

            case 'i':
            {
                std::int8_t number;
                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
                {
                    return false;
                }
                result = static_cast<std::size_t>(number);
                return true;
            }

            case 'I':
            {
                std::int16_t number;
                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
                {
                    return false;
                }
                result = static_cast<std::size_t>(number);
                return true;
            }

            case 'l':
            {
                std::int32_t number;
                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
                {
                    return false;
                }
                result = static_cast<std::size_t>(number);
                return true;
            }

            case 'L':
            {
                std::int64_t number;
                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
                {
                    return false;
                }
                result = static_cast<std::size_t>(number);
                return true;
            }

            default:
            {
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "expected length type specification (U, i, I, l, L) after '#'; last byte: 0x" + last_token, "size")));
            }
        }
    }

    /*!
    @brief determine the type and size for a container

    In the optimized UBJSON format, a type and a size can be provided to allow
    for a more compact representation.

    @param[out] result  pair of the size and the type

    @return whether pair creation completed
    */
    bool get_ubjson_size_type(std::pair<std::size_t, int>& result)
    {
        result.first = string_t::npos; // size
        result.second = 0; // type

        get_ignore_noop();

        if (current == '$')
        {
            result.second = get();  // must not ignore 'N', because 'N' maybe the type
            if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "type")))
            {
                return false;
            }

            get_ignore_noop();
            if (JSON_UNLIKELY(current != '#'))
            {
                if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "value")))
                {
                    return false;
                }
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::ubjson, "expected '#' after type information; last byte: 0x" + last_token, "size")));
            }

            return get_ubjson_size_value(result.first);
        }

        if (current == '#')
        {
            return get_ubjson_size_value(result.first);
        }

        return true;
    }

    /*!
    @param prefix  the previously read or set type prefix
    @return whether value creation completed
    */
    bool get_ubjson_value(const int prefix)
    {
        switch (prefix)
        {
            case std::char_traits<char>::eof():  // EOF
                return unexpect_eof(input_format_t::ubjson, "value");

            case 'T':  // true
                return sax->boolean(true);
            case 'F':  // false
                return sax->boolean(false);

            case 'Z':  // null
                return sax->null();

            case 'U':
            {
                std::uint8_t number;
                return get_number(input_format_t::ubjson, number) and sax->number_unsigned(number);
            }

            case 'i':
            {
                std::int8_t number;
                return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
            }

            case 'I':
            {
                std::int16_t number;
                return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
            }

            case 'l':
            {
                std::int32_t number;
                return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
            }

            case 'L':
            {
                std::int64_t number;
                return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
            }

            case 'd':
            {
                float number;
                return get_number(input_format_t::ubjson, number) and sax->number_float(static_cast<number_float_t>(number), "");
            }

            case 'D':
            {
                double number;
                return get_number(input_format_t::ubjson, number) and sax->number_float(static_cast<number_float_t>(number), "");
            }

            case 'C':  // char
            {
                get();
                if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "char")))
                {
                    return false;
                }
                if (JSON_UNLIKELY(current > 127))
                {
                    auto last_token = get_token_string();
                    return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "byte after 'C' must be in range 0x00..0x7F; last byte: 0x" + last_token, "char")));
                }
                string_t s(1, static_cast<char>(current));
                return sax->string(s);
            }

            case 'S':  // string
            {
                string_t s;
                return get_ubjson_string(s) and sax->string(s);
            }

            case '[':  // array
                return get_ubjson_array();

            case '{':  // object
                return get_ubjson_object();

            default: // anything else
            {
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::ubjson, "invalid byte: 0x" + last_token, "value")));
            }
        }
    }

    /*!
    @return whether array creation completed
    */
    bool get_ubjson_array()
    {
        std::pair<std::size_t, int> size_and_type;
        if (JSON_UNLIKELY(not get_ubjson_size_type(size_and_type)))
        {
            return false;
        }

        if (size_and_type.first != string_t::npos)
        {
            if (JSON_UNLIKELY(not sax->start_array(size_and_type.first)))
            {
                return false;
            }

            if (size_and_type.second != 0)
            {
                if (size_and_type.second != 'N')
                {
                    for (std::size_t i = 0; i < size_and_type.first; ++i)
                    {
                        if (JSON_UNLIKELY(not get_ubjson_value(size_and_type.second)))
                        {
                            return false;
                        }
                    }
                }
            }
            else
            {
                for (std::size_t i = 0; i < size_and_type.first; ++i)
                {
                    if (JSON_UNLIKELY(not parse_ubjson_internal()))
                    {
                        return false;
                    }
                }
            }
        }
        else
        {
            if (JSON_UNLIKELY(not sax->start_array(std::size_t(-1))))
            {
                return false;
            }

            while (current != ']')
            {
                if (JSON_UNLIKELY(not parse_ubjson_internal(false)))
                {
                    return false;
                }
                get_ignore_noop();
            }
        }

        return sax->end_array();
    }

    /*!
    @return whether object creation completed
    */
    bool get_ubjson_object()
    {
        std::pair<std::size_t, int> size_and_type;
        if (JSON_UNLIKELY(not get_ubjson_size_type(size_and_type)))
        {
            return false;
        }

        string_t key;
        if (size_and_type.first != string_t::npos)
        {
            if (JSON_UNLIKELY(not sax->start_object(size_and_type.first)))
            {
                return false;
            }

            if (size_and_type.second != 0)
            {
                for (std::size_t i = 0; i < size_and_type.first; ++i)
                {
                    if (JSON_UNLIKELY(not get_ubjson_string(key) or not sax->key(key)))
                    {
                        return false;
                    }
                    if (JSON_UNLIKELY(not get_ubjson_value(size_and_type.second)))
                    {
                        return false;
                    }
                    key.clear();
                }
            }
            else
            {
                for (std::size_t i = 0; i < size_and_type.first; ++i)
                {
                    if (JSON_UNLIKELY(not get_ubjson_string(key) or not sax->key(key)))
                    {
                        return false;
                    }
                    if (JSON_UNLIKELY(not parse_ubjson_internal()))
                    {
                        return false;
                    }
                    key.clear();
                }
            }
        }
        else
        {
            if (JSON_UNLIKELY(not sax->start_object(std::size_t(-1))))
            {
                return false;
            }

            while (current != '}')
            {
                if (JSON_UNLIKELY(not get_ubjson_string(key, false) or not sax->key(key)))
                {
                    return false;
                }
                if (JSON_UNLIKELY(not parse_ubjson_internal()))
                {
                    return false;
                }
                get_ignore_noop();
                key.clear();
            }
        }

        return sax->end_object();
    }

    ///////////////////////
    // Utility functions //
    ///////////////////////

    /*!
    @brief get next character from the input

    This function provides the interface to the used input adapter. It does
    not throw in case the input reached EOF, but returns a -'ve valued
    `std::char_traits<char>::eof()` in that case.

    @return character read from the input
    */
    int get()
    {
        ++chars_read;
        return current = ia->get_character();
    }

    /*!
    @return character read from the input after ignoring all 'N' entries
    */
    int get_ignore_noop()
    {
        do
        {
            get();
        }
        while (current == 'N');

        return current;
    }

    /*
    @brief read a number from the input

    @tparam NumberType the type of the number
    @param[in] format   the current format (for diagnostics)
    @param[out] result  number of type @a NumberType

    @return whether conversion completed

    @note This function needs to respect the system's endianess, because
          bytes in CBOR, MessagePack, and UBJSON are stored in network order
          (big endian) and therefore need reordering on little endian systems.
    */
    template<typename NumberType, bool InputIsLittleEndian = false>
    bool get_number(const input_format_t format, NumberType& result)
    {
        // step 1: read input into array with system's byte order
        std::array<std::uint8_t, sizeof(NumberType)> vec;
        for (std::size_t i = 0; i < sizeof(NumberType); ++i)


Coverage Report

Created: 2023-11-19 07:17