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 bool nlohmann::basic_json< ObjectType, ArrayType, StringType, BooleanType, NumberIntegerType, NumberUnsignedType, NumberFloatType, AllocatorType, JSONSerializer, BinaryType >::accept |
( |
InputType && |
i, |
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|
const bool |
ignore_comments = false |
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) |
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inlinestatic |
Unlike the parse(InputType&&, const parser_callback_t,const bool) function, this function neither throws an exception in case of invalid JSON input (i.e., a parse error) nor creates diagnostic information.
- 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.
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- Parameters
-
[in] | i | input to read from |
[in] | ignore_comments | whether comments should be ignored and treated like whitespace (true) or yield a parse error (true); (optional, false by default) |
- Returns
- Whether the input read from i is valid JSON.
- Complexity
- Linear in the length of the input. The parser is a predictive LL(1) parser.
- Note
- A UTF-8 byte order mark is silently ignored.
- Example
- The example below demonstrates the
accept()
function reading from a string.
3#include <nlohmann/json.hpp>
17 auto invalid_text = R
"(
19 "strings": ["extra", "comma", ]
23 std::cout << std::boolalpha
static bool accept(InputType &&i, const bool ignore_comments=false)
check if the input is valid JSON
basic_json<> json
default JSON class
Output (play with this example online): true false
The example code above can be translated with g++ -std=c++11 -Isingle_include doc/examples/accept__string.cpp -o accept__string
Definition at line 24500 of file json.hpp.