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std::is_member_object_pointer - cppreference.com

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template< class T > struct is_member_object_pointer;

 (since C++11)

std::is_member_object_pointer is a UnaryTypeTrait.

Checks whether T is a non-static member object pointer. Provides the member constant value which is equal to true, if T is a non-static member object pointer type. Otherwise, value is equal to false.

If the program adds specializations for std::is_member_object_pointer or std::is_member_object_pointer_v, the behavior is undefined.

Template parameters

Helper variable template

template< class T > constexpr bool is_member_object_pointer_v = is_member_object_pointer<T>::value;

 (since C++17)

Inherited from std::integral_constant

Member constants

true if T is a pointer to member object, false otherwise
(public static member constant)

Member functions

converts the object to bool, returns value
(public member function)
returns value
(public member function)

Member types

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

Possible implementation

template<class T>
struct is_member_object_pointer : std::integral_constant<
                                      bool,
                                      std::is_member_pointer<T>::value &&
                                      !std::is_member_function_pointer<T>::value
                                  > {};

Example

#include <iostream>
#include <type_traits>

int main()
{
    class C {};
    std::cout << "Is member object pointer?\n" << std::boolalpha
              << std::is_member_object_pointer_v<int(C::*)>
              << ": int(C::*)\n"
              << std::is_member_object_pointer_v<int(C::*)()>
              << ": int(C::*)()\n";
}

Output: 

Is member object pointer?
true: int(C::*)
false: int(C::*)()

See also