std::is_member_function_pointer
Defined in header <type_traits> | ||
|---|---|---|
template< class T > struct is_member_function_pointer; | (since C++11) |
std::is_member_function_pointer is a UnaryTypeTrait.
Checks whether T is a non-static member function pointer. Provides the member constant value which is equal to true, if T is a non-static member function pointer type. Otherwise, value is equal to false.
If the program adds specializations for std::is_member_function_pointer or std::is_member_function_pointer_v, the behavior is undefined.
Template parameters
| T | - | a type to check |
Helper variable template
template< class T >
constexpr bool is_member_function_pointer_v =
is_member_function_pointer<T>::value;
| (since C++17) |
Inherited from std::integral_constant
Member constants
|
value
[static] |
true if T is a member function 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_type | bool |
type | std::integral_constant<bool,value> |
Possible implementation
template<class T>
struct is_member_function_pointer_helper : std::false_type {};
template<class T, class U>
struct is_member_function_pointer_helper<T U::*> : std::is_function<T> {};
template<class T>
struct is_member_function_pointer
: is_member_function_pointer_helper<typename std::remove_cv<T>::type> {};
|
Example
#include <type_traits>
class A
{
public:
void member() {}
};
int main()
{
// fails at compile time if A::member is a data member and not a function
static_assert(std::is_member_function_pointer<decltype(&A::member)>::value,
"A::member is not a member function.");
}
See also
|
(C++11) | checks if a type is a pointer type (class template) |
|
(C++11) | checks if a type is a non-static member object pointer (class template) |
|
(C++11) | checks if a type is a pointer to a non-static member function or object (class template) |
|
(C++26) | checks if reflection represents a member function pointer type (function) |
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