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

NAME
     std::is_member_object_pointer - std::is_member_object_pointer

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

	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
	T - a type to check

	Helper variable template

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

     Inherited from std::integral_constant

Member constants
	value	 true if T is a pointer to member object, 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_object_pointer : std::integral_constant<
					      bool,
					      std::is_member_pointer<T>::value
     &&
					      !std::is_member_func-
     tion_pointer<T>::value
					  > {};

Example
     // Run this code

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

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