parse() [2/3]

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 BinaryType = std::vector<std::uint8_t>>

template<typename InputType >

static JSON_HEDLEY_WARN_UNUSED_RESULT basic_json nlohmann::basic_json< ObjectType, ArrayType, StringType, BooleanType, NumberIntegerType, NumberUnsignedType, NumberFloatType, AllocatorType, JSONSerializer, BinaryType >::parse ( InputType &&  i, const parser_callback_t  cb = nullptr, const bool  allow_exceptions = true, const bool  ignore_comments = false  )

inlinestatic

deserialize from a compatible input

Template Parameters

InputType

A compatible input, for instance an std::istream object a FILE pointer a C-style array of characters a pointer to a null-terminated string of single byte characters an object obj for which begin(obj) and end(obj) produces a valid pair of iterators.

Parameters

[in]	i	input to read from
[in]	cb	a parser callback function of type parser_callback_t which is used to control the deserialization by filtering unwanted values (optional)
[in]	allow_exceptions	whether to throw exceptions in case of a parse error (optional, true by default)
[in]	ignore_comments	whether comments should be ignored and treated like whitespace (true) or yield a parse error (true); (optional, false by default)

Returns

deserialized JSON value; in case of a parse error and allow_exceptions set to false, the return value will be value_t::discarded.

Exceptions

parse_error.101	if a parse error occurs; example: ""unexpected end of input; expected string literal""
parse_error.102	if to_unicode fails or surrogate error
parse_error.103	if to_unicode fails

@complexity Linear in the length of the input. The parser is a predictive LL(1) parser. The complexity can be higher if the parser callback function cb or reading from the input i has a super-linear complexity.

Note

A UTF-8 byte order mark is silently ignored.

@liveexample{The example below demonstrates the parse() function reading from an array.,parse__array__parser_callback_t}

@liveexample{The example below demonstrates the parse() function with and without callback function.,parse__string__parser_callback_t}

@liveexample{The example below demonstrates the parse() function with and without callback function.,parse__istream__parser_callback_t}

@liveexample{The example below demonstrates the parse() function reading from a contiguous container.,parse__contiguouscontainer__parser_callback_t}

Since

version 2.0.3 (contiguous containers); version 3.9.0 allowed to ignore comments.

Definition at line 24605 of file json.hpp.

    {
        basic_json result;
        parser(detail::input_adapter(std::forward<InputType>(i)), cb, allow_exceptions, ignore_comments).parse(true, result);
        return result;
    }