std::is_member_object_pointer
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 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
.
The behavior of a program that adds specializations for is_member_object_pointer
or is_member_object_pointer_v
(since C++17) is undefined.
Template parameters
T | - | a type to check |
Helper variable template
template< class T > inline constexpr bool is_member_object_pointer_v = is_member_object_pointer<T>::value; |
(since C++17) |
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> |
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
#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
See also
(C++11)
|
checks if a type is a pointer type (class template) |
(C++11)
|
checks if a type is a pointer to an non-static member function or object (class template) |
(C++11)
|
checks if a type is a pointer to a non-static member function (class template) |
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