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      std::is_member_pointer

      From cppreference.com
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      is_member_pointer
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      Compile-time rational arithmetic
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      Defined in header <type_traits>
      template<class T >
      struct is_member_pointer;
      		(since C++11)

      std::is_member_pointer is a UnaryTypeTrait.

      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.

      If the program adds specializations for std::is_member_pointer or std::is_member_pointer_v, the behavior is undefined.

      Contents

      [edit]Template parameters

      T - a type to check

      [edit]Helper variable template

      template<class T >
      constexprbool is_member_pointer_v = is_member_pointer<T>::value;
      		(since C++17)
      [edit]

      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_typebool
      typestd::integral_constant<bool, value>

      [edit]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<typenamestd::remove_cv<T>::type>{};

      [edit]Example

      Run this code
      #include <cassert>#include <type_traits>   static_assert(!std::is_member_pointer_v<int*>);   struct S {int i{42};int foo(){return0xF00;}};using mem_int_ptr_t =int S::*;using mem_fun_ptr_t =int(S::*)(); static_assert(std::is_member_pointer_v<mem_int_ptr_t>); static_assert(std::is_member_pointer_v<mem_fun_ptr_t>);   int main(){ S s;   mem_int_ptr_t pm =&S::i;assert(s.i== s.*pm);   mem_fun_ptr_t pmf =&S::foo;assert((s.*pmf)()== s.foo());}

      [edit]See also

      (C++11)
      		 checks if a type is a pointer type
      (class template)[edit]
      (C++11)
      		 checks if a type is a non-static member object pointer
      (class template)[edit]
      (C++11)
      		 checks if a type is a non-static member function pointer
      (class template)[edit]
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