NAME¶

std::is_member_pointer - std::is_member_pointer

Synopsis¶

Defined in header <type_traits>
template< class T > (since C++11)
struct is_member_pointer;

If T is pointer to non-static member object or a pointer to non-static member
function, provides the member constant value equal true. For any other type, value
is false.

The behavior of a program that adds specializations for is_member_pointer
or is_member_pointer_v
(since C++17) is undefined.

Template parameters¶

T - a type to check

Helper variable template

template< class T >
inline constexpr bool is_member_pointer_v = (since C++17)
is_member_pointer<T>::value;

Inherited from std::integral_constant

Member constants¶

value true if T is a member pointer type , false otherwise
[static] (public static member constant)

Member functions¶

operator bool converts the object to bool, returns value
(public member function)
operator() returns value
(C++14) (public member function)

Member types¶

Type Definition
value_type bool
type std::integral_constant<bool, value>

Possible implementation¶

template< class T >
struct is_member_pointer_helper : std::false_type {};

template< class T, class U >
struct is_member_pointer_helper<T U::*> : std::true_type {};

template< class T >
struct is_member_pointer :
is_member_pointer_helper<typename std::remove_cv<T>::type> {};

Example¶

// Run this code

#include <iostream>
#include <type_traits>

int main() {
class cls {};
std::cout << (std::is_member_pointer<int(cls::*)>::value
? "T is member pointer"
: "T is not a member pointer") << '\n';
std::cout << (std::is_member_pointer<int>::value
? "T is member pointer"
: "T is not a member pointer") << '\n';
}

Output:¶

T is member pointer
T is not a member pointer

See also¶

is_pointer checks if a type is a pointer type
(C++11) (class template)
is_member_object_pointer checks if a type is a pointer to a non-static member
(C++11) object
(class template)
is_member_function_pointer checks if a type is a pointer to a non-static member
(C++11) function
(class template)