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std::is_member_function_pointer - cppreference.com

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template< class T > struct is_member_function_pointer;

 (since C++11)

std::is_member_function_pointer is a UnaryTypeTrait.

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

If the program adds specializations for std::is_member_function_pointer or std::is_member_function_pointer_v, the behavior is undefined.

Template parameters

Helper variable template

template< class T > constexpr bool is_member_function_pointer_v = is_member_function_pointer<T>::value;

 (since C++17)

Inherited from std::integral_constant

Member constants

true if T is a member function pointer type, 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_function_pointer_helper : std::false_type {};

template<class T, class U>
struct is_member_function_pointer_helper<T U::*> : std::is_function<T> {};

template<class T>
struct is_member_function_pointer 
    : is_member_function_pointer_helper<typename std::remove_cv<T>::type> {};

Example

#include <type_traits>

class A
{
public:
    void member() {}
};

int main()
{
    // fails at compile time if A::member is a data member and not a function
    static_assert(std::is_member_function_pointer<decltype(&A::member)>::value,
                  "A::member is not a member function."); 
}

See also