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add_pointer Class

Makes a pointer-to-type from a specified type.

Syntax

template <class T>
struct add_pointer;

template <class T>
using add_pointer_t = typename add_pointer<T>::type;

Parameters

T
The type to modify.

Remarks

The member typedef type names the same type as remove_reference<T>::type*. The alias add_pointer_t is a shortcut to access the member typedef type.

Because it is invalid to make a pointer from a reference, add_pointer removes the reference, if any, from the specified type before it makes a pointer-to-type. Consequently, you can use a type with add_pointer without being concerned about whether the type is a reference.

Example

The following example demonstrates that add_pointer of a type is the same as a pointer to that type.

#include <type_traits>
#include <iostream>

int main()
{
    std::add_pointer_t<int> *p = (int **)0;

    p = p;  // to quiet "unused" warning
    std::cout << "add_pointer_t<int> == "
        << typeid(*p).name() << std::endl;

    return (0);
}
add_pointer_t<int> == int *

Requirements

Header: <type_traits>

Namespace: std

See also

<type_traits>
remove_pointer Class