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std::remove_pointer

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

Provides the member typedef type which is the type pointed to by T, or, if T is not a pointer, then type is the same as T.

The behavior of a program that adds specializations for remove_pointer is undefined.

Member types

Name Definition
type the type pointed to by T or T if it's not a pointer

Helper types

template< class T >
using remove_pointer_t = typename remove_pointer<T>::type;
(since C++14)

Possible implementation

template< class T > struct remove_pointer                    {typedef T type;};
template< class T > struct remove_pointer<T*>                {typedef T type;};
template< class T > struct remove_pointer<T* const>          {typedef T type;};
template< class T > struct remove_pointer<T* volatile>       {typedef T type;};
template< class T > struct remove_pointer<T* const volatile> {typedef T type;};

Example

#include <iostream>
#include <type_traits>
 
template<class T1, class T2>
void print_is_same() 
{
    std::cout << std::is_same<T1, T2>() << '\n';
}
 
void print_separator() 
{
    std::cout << "-----\n";
}
 
int main() 
{
    std::cout << std::boolalpha;
 
    print_is_same<int, int>();   // true
    print_is_same<int, int*>();  // false
    print_is_same<int, int**>(); // false
 
    print_separator();
 
    print_is_same<int, std::remove_pointer<int>::type>();   // true
    print_is_same<int, std::remove_pointer<int*>::type>();  // true
    print_is_same<int, std::remove_pointer<int**>::type>(); // false
 
    print_separator();
 
    print_is_same<int, std::remove_pointer<int* const>::type>();          // true
    print_is_same<int, std::remove_pointer<int* volatile>::type>();       // true
    print_is_same<int, std::remove_pointer<int* const volatile>::type>(); // true
}

Output:

true
false
false
-----
true
true
false
-----
true
true
true

See also

(C++11)
checks if a type is a pointer type
(class template)
(C++11)
adds a pointer to the given type
(class template)

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