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_function_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)