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std::is_mem...tion_pointer(3)  C++ Standard Libary std::is_mem...tion_pointer(3)

NAME
     std::is_member_function_pointer - std::is_member_function_pointer

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

	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 func-
     tion 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
	T - a type to check

	Helper variable template

	template< class T >

	inline constexpr bool is_member_function_pointer_v =  (since C++17)

	    is_member_function_pointer<T>::value;

     Inherited from std::integral_constant

Member constants
	value	 true if T is a member function 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_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::re-
     move_cv<T>::type> {};

Example
     // Run this code

      #include <type_traits>

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

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

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

http://cppreference.com 	   2024.06.10	   std::is_mem...tion_pointer(3)
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