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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.

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

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;
};

Notes

Feature-test macro	Value	Std	Comment
`__cpp_lib_remove_cvref`	201711L	(C++20)	`std::remove_cvref`

Example

#include <type_traits>
 
int main()
{
    static_assert(std::is_same_v<std::remove_cvref_t<int>, int>);
    static_assert(std::is_same_v<std::remove_cvref_t<int&>, int>);
    static_assert(std::is_same_v<std::remove_cvref_t<int&&>, int>);
    static_assert(std::is_same_v<std::remove_cvref_t<const int&>, int>);
    static_assert(std::is_same_v<std::remove_cvref_t<const int[2]>, int[2]>);
    static_assert(std::is_same_v<std::remove_cvref_t<const int(&)[2]>, int[2]>);
    static_assert(std::is_same_v<std::remove_cvref_t<int(int)>, int(int)>);
}

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