C++

Reference

<type_traits>

class template
<type_traits>

std::is_member_pointer

template <class T> struct is_member_pointer;
Is member pointer type

Trait class that identifies whether T is a pointer to a non-static member.

It inherits from integral_constant as being either true_type or false_type, depending on whether T is either a pointer to a non-static data member or a pointer to a non-static member function.

This is a compound type trait defined with the same behavior as:
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template<class T>
struct is_member_pointer : std::integral_constant < bool,
    is_member_object_pointer<T>::value || is_member_function_pointer<T>::value> {};

Template parameters

T
A type.

Member types

Inherited from integral_constant:
member typedefinition
value_typebool
typeeither true_type or false_type

Member constants

Inherited from integral_constant:
member constantdefinition
valueeither true or false

Member functions

Inherited from integral_constant:
operator bool
Returns value (public member function)

Example

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// is_member_pointer example
#include <iostream>
#include <type_traits>

struct A { int x; };

int main() {
  int A::* pt = &A::x;
  std::cout << std::boolalpha;
  std::cout << "is_member_pointer:" << std::endl;
  std::cout << "A*: " << std::is_member_pointer<A*>::value << std::endl;
  std::cout << "int A::*: " << std::is_member_pointer<int A::*>::value << std::endl;
  std::cout << "void(A::*)(): " << std::is_member_pointer<void(A::*)()>::value << std::endl;
  std::cout << "decltype(pt): " << std::is_member_pointer<decltype(pt)>::value << std::endl;
  return 0;
}

Output:
is_member_pointer:
A*: false
int A::*: true
void(A::*)(): true
decltype(pt): true


See also

is_member_object_pointer
Is member object pointer (class template)
is_member_function_pointer
Is member function pointer (class template)
is_pointer
Is pointer (class template)