std::remove_cvref

Defined in header <type_traits> 
template< class T >
struct remove_cvref;
 (since C++20)

If the type T is a reference type, provides the member typedef type which is the type referred to by T with its topmost cv-qualifiers removed. Otherwise type is T with its topmost cv-qualifiers removed.

Member types

Name Definition
type the type referred by T or T itself if it is not a reference, with top-level cv-qualifiers removed

Helper types

template< class T >
using remove_cvref_t = typename remove_cvref<T>::type;
 (since C++20)

Possible implementation

template< class T >
struct remove_cvref {
    typedef std::remove_cv_t<std::remove_reference_t<T>> type;
};

Example

#include <iostream>
#include <type_traits>
 
int main()
{
    std::cout << std::boolalpha
              << std::is_same_v<std::remove_cvref_t<int>, int> << '\n'
              << std::is_same_v<std::remove_cvref_t<int&>, int> << '\n'
              << std::is_same_v<std::remove_cvref_t<int&&>, int> << '\n'
              << std::is_same_v<std::remove_cvref_t<const int&>, int> << '\n'
              << std::is_same_v<std::remove_cvref_t<const int[2]>, int[2]> << '\n'
              << std::is_same_v<std::remove_cvref_t<const int(&)[2]>, int[2]> << '\n'
              << std::is_same_v<std::remove_cvref_t<int(int)>, int(int)> << '\n';
}

Output:

true
true
true
true
true
true
true

See also

(C++11)(C++11)(C++11)
 removes const or/and volatile specifiers from the given type
(class template)
(C++11)
 removes a reference from the given type
(class template)
(C++11)
 applies type transformations as when passing a function argument by value
(class template)

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