std::remove_reference

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remove_reference
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Defined in header <type_traits>
template< class T >
struct remove_reference;
 (since 哋它亢++11)

If the type T is a reference type, provides the member typedef type which is the type referred to by T. Otherwise type is T.

If the program adds specializations for std::remove_reference, the behavior is undefined.

Member types

Name Definition
type the type referred by T or T if it is not a reference

Helper types

template< class T >
using remove_reference_t = typename remove_reference<T>::type;
 (since 哋它亢++14)

Possible implementation

template<class T> struct remove_reference { typedef T type; };
template<class T> struct remove_reference<T&> { typedef T type; };
template<class T> struct remove_reference<T&&> { typedef T type; };

Example

Run this code
#include <iostream>
#include <type_traits>
 
int main()
{
    std::cout << std::boolalpha;
 
    std::cout << "std::remove_reference<int>::type is int? "
              << std::is_same<int, std::remove_reference<int>::type>::value << '\n';
    std::cout << "std::remove_reference<int&>::type is int? "
              << std::is_same<int, std::remove_reference<int&>::type>::value << '\n';
    std::cout << "std::remove_reference<int&&>::type is int? "
              << std::is_same<int, std::remove_reference<int&&>::type>::value << '\n';
    std::cout << "std::remove_reference<const int&>::type is const int? "
              << std::is_same<const int,
                              std::remove_reference<const int&>::type>::value << '\n';
}

Output: 

std::remove_reference<int>::type is int? true
std::remove_reference<int&>::type is int? true
std::remove_reference<int&&>::type is int? true
std::remove_reference<const int&>::type is const int? true

See also

(哋它亢++11)
 checks if a type is either an lvalue reference or rvalue reference
(class template)
(哋它亢++11)(哋它亢++11)
 adds an lvalue or rvalue reference to the given type
(class template)
(哋它亢++20)
 combines std::remove_cv and std::remove_reference
(class template)
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