constexpr bool is_null() const noexcept;
This function returns #!cpp true
if and only if the JSON value is #!json null
.
#!cpp true
if type is #!json null
, #!cpp false
otherwise.
No-throw guarantee: this member function never throws exceptions.
Constant.
??? example
The following code exemplifies `is_null()` for all JSON types. ```cpp --8<-- "examples/is_null.cpp" ``` Output: ```json --8<-- "examples/is_null.output" ```