std::is_member_object_pointer - cppreference.com

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# std::is_member_object_pointer

From cppreference.com
< cpp‎ | types

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

Checks whether `T` is a non-static member object. Provides the member constant `value` which is equal to true, if `T` is a non-static member object type. Otherwise, `value` is equal to false.

### [edit] Template parameters

T | - | a type to check

### [edit] Helper variable template

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

[edit]

## Inherited from std::integral_constant

### Member constants

value [static] | true if `T` is a pointer to member object , 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_type` | `bool`
`type` | std::integral_constant<bool, value>

### [edit] 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
                                      > {};

### [edit] Example

| This section is incomplete Reason: simplify

Run this code

    #include <iostream>
    #include <type_traits>

    int main() {
        class cls {};
        std::cout << (std::is_member_object_pointer<int(cls::*)>::value
                         ? "T is member object pointer"
                         : "T is not a member object pointer") << '\n';
        std::cout << (std::is_member_object_pointer<int(cls::*)()>::value
                         ? "T is member object pointer"
                         : "T is not a member object pointer") << '\n';
    }

Output:

    T is member object pointer
    T is not a member object pointer

### [edit] See also

is_pointer (C++11) | checks if a type is a pointer type (class template) [edit]
is_member_pointer (C++11) | checks if a type is a pointer to a non-static member function or object (class template) [edit]
is_member_function_pointer (C++11) | checks if a type is a pointer to a non-static member function (class template) [edit]
std::experimental::is_member_object_pointer_v (library fundamentals TS) | variable template alias of `std::is_member_object_pointer::value` (variable template) [edit]

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