std::is_member_function_pointer (3) - Linux Manuals

std::is_member_function_pointer: std::is_member_function_pointer

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;

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.

Template parameters

T - a type to check

Helper variable template

template< class T > (since C++17)
inline constexpr bool is_member_function_pointer_v = 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
         (public static member constant)
[static]

Member functions

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

operator() returns value
              (public member function)
(C++14)

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< std::remove_cv_t<T> > {};

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 function
      static_assert(std::is_member_function_pointer<decltype(&A::member)>::value,
                    "A::member is not a member function.");
  }