# std::is_member_pointer

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< cpp‎ | types

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

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.

### Template parameters

T | - | a type to check

### Helper variable template

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

## Inherited from std::integral_constant

### Member constants

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

### Member functions

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

| This section is incomplete Reason: simplify

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

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