std::remove_reference

 

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Compile-time rational arithmetic
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integer_sequence (C++14)

 

Defined in header <type_traits>
template< class T > struct remove_reference;		(since C++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.

The behavior of a program that adds specializations for std::remove_reference 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 C++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

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