std::is_pointer

 

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

If T is an object pointer type or a function pointer type (but not pointer to non-static member object or member function), provides the member constant value equal true. For any other type, value is false.

Inherited from std::integral_constant

Member constants

value [static]	true if T is a pointer type , false otherwise (public static member constant)

Member functions

operator bool	converts the object to bool, 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_pointer_helper : std::false_type {}; template< class T > struct is_pointer_helper<T*> : std::true_type {}; template< class T > struct is_pointer : is_pointer_helper<typename std::remove_cv<T>::type> {};

Example

#include <iostream>
#include <type_traits>
 
class A {};
 
int main() 
{
    std::cout << std::boolalpha;
    std::cout << std::is_pointer<A>::value << '\n';
    std::cout << std::is_pointer<A*>::value << '\n';
    std::cout << std::is_pointer<float>::value << '\n';
    std::cout << std::is_pointer<int>::value << '\n';
    std::cout << std::is_pointer<int*>::value << '\n';
    std::cout << std::is_pointer<int**>::value << '\n';
}

Output:

false
true
false
false
true
true

See also

is_array (C++11)	checks if a type is an array type (class template)
is_scalar (C++11)	checks if a type is scalar type (class template)