std::remove_cvref

 

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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.

If the program adds specializations for std::remove_cvref, the behavior 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 = remove_cvref<T>::type;		(since C++20)

Possible implementation

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

Notes

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

Example

Run this code

#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<constint&>, int>); static_assert(std::is_same_v<std::remove_cvref_t<constint[2]>, int[2]>); static_assert(std::is_same_v<std::remove_cvref_t<constint(&)[2]>, int[2]>); static_assert(std::is_same_v<std::remove_cvref_t<int(int)>, int(int)>);}

See also

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)