// (1) template<typename InputType> static basic_json parse(InputType&& i, const parser_callback_t cb = nullptr, const bool allow_exceptions = true, const bool ignore_comments = false) // (2) template<typename IteratorType> static basic_json parse(IteratorType first, IteratorType last, const parser_callback_t cb = nullptr, const bool allow_exceptions = true, const bool ignore_comments = false)
Deserialize from a compatible input.
Deserialize from a pair of character iterators
The value_type of the iterator must be a integral type with size of 1, 2 or 4 bytes, which will be interpreted respectively as UTF-8, UTF-16 and UTF-32.
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.
IteratorType
: Description
i
(in) : Input to parse from.
cb
(in) : a parser callback function of type parser_callback_t
which is used to control the deserialization by filtering unwanted values (optional)
allow_exceptions
(in) : whether to throw exceptions in case of a parse error (optional, #!cpp true
by default)
ignore_comments
(in) : whether comments should be ignored and treated like whitespace (#!cpp true
) or yield a parse error (#!cpp false
); (optional, #!cpp false
by default)
first
(in) : iterator to start of character range
last
(in) : iterator to end of character range
Deserialized JSON value; in case of a parse error and allow_exceptions
set to #!cpp false
, the return value will be value_t::discarded
.
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 (1) the input i
or (2) the iterator range [first
, last
] has a super-linear complexity.
(1) A UTF-8 byte order mark is silently ignored.
??? example
The example below demonstrates the `parse()` function reading from an array. ```cpp --8<-- "examples/parse__array__parser_callback_t.cpp" ``` Output: ```json --8<-- "examples/parse__array__parser_callback_t.output" ```
??? example
The example below demonstrates the `parse()` function with and without callback function. ```cpp --8<-- "examples/parse__string__parser_callback_t.cpp" ``` Output: ```json --8<-- "examples/parse__string__parser_callback_t.output" ```
??? example
The example below demonstrates the `parse()` function with and without callback function. ```cpp --8<-- "examples/parse__istream__parser_callback_t.cpp" ``` Output: ```json --8<-- "examples/parse__istream__parser_callback_t.output" ```
??? example
The example below demonstrates the `parse()` function reading from a contiguous container. ```cpp --8<-- "examples/parse__contiguouscontainer__parser_callback_t.cpp" ``` Output: ```json --8<-- "examples/parse__contiguouscontainer__parser_callback_t.output" ```
(1) version 2.0.3 (contiguous containers); version 3.9.0 allowed to ignore comments.