std::meta::is_null_pointer_type

 

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Defined in header <meta>
consteval bool is_null_pointer_type( std::meta::info r );		(since C++26)

Returns true if r represents (possibly cv-qualified) std::nullptr_t type. Otherwise returns false.

Parameters

r

-

a reflection value

Return value

true if r represents std::nullptr_t type; otherwise false.

Exceptions

Throws std::meta::exception if r does not represent a type or type alias.

Example

Run this code

#include <meta>

static_assert
(""
    and is_null_pointer_type(^^decltype(nullptr)) == true
    and is_null_pointer_type(^^const std::nullptr_t) == true
    and is_null_pointer_type(^^volatile decltype(nullptr)) == true
    and is_null_pointer_type(std::meta::add_cv(^^decltype(nullptr))) == true
    and is_null_pointer_type(^^int*) == false
    and is_null_pointer_type(^^void) == false
    and is_null_pointer_type(^^void*) == false
);

int main() {}

See also

is_pointer_type (C++26)	checks if reflected type is a pointer type (function)
is_array_type (C++26)	checks if reflected type is an array type (function)
is_null_pointer (C++11)(DR*)	checks if a type is std::nullptr_t (class template)