basic_json() [1/10]

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>>

nlohmann::basic_json< ObjectType, ArrayType, StringType, BooleanType, NumberIntegerType, NumberUnsignedType, NumberFloatType, AllocatorType, JSONSerializer, BinaryType >::basic_json ( const value_t  v )

inline

create an empty value with a given type

Create an empty JSON value with a given type. The value will be default initialized with an empty value which depends on the type:

Value type	initial value
null	null
boolean	false
string	""
number	0
object	{}
array	[]
binary	empty array

Parameters

[in]

v

the type of the value to create

@complexity Constant.

@exceptionsafety Strong guarantee: if an exception is thrown, there are no changes to any JSON value.

@liveexample{The following code shows the constructor for different value_t values,basic_json__value_t}

See also

see clear() – restores the postcondition of this constructor

Since

version 1.0.0

Definition at line 19164 of file json.hpp.

        : m_type(v), m_value(v)
    {
        assert_invariant();
    }