std::remove_cv, std::remove_const, std::remove_volatile

 

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Type modifications
remove_cvremove_constremove_volatile (C++11)(C++11)(C++11) add_cvadd_constadd_volatile (C++11)(C++11)(C++11) make_signed (C++11) make_unsigned (C++11)	remove_reference (C++11) add_lvalue_referenceadd_rvalue_reference (C++11)(C++11) remove_pointer (C++11) add_pointer (C++11) remove_extent (C++11) remove_all_extents (C++11)
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Defined in header <type_traits>
template< class T > struct remove_cv;	(1)	(since C++11)
template< class T > struct remove_const;	(2)	(since C++11)
template< class T > struct remove_volatile;	(3)	(since C++11)

Provides the member typedef type which is the same as T, except that its topmost cv-qualifiers are removed.

1) removes the topmost const, the topmost volatile, or both, if present.

2) removes the topmost const

3) removes the topmost volatile

Member types

Name	Definition
type	the type T without cv-qualifier

Helper types

template< class T > using remove_cv_t       = typename remove_cv<T>::type;		(since C++14)
template< class T > using remove_const_t    = typename remove_const<T>::type;		(since C++14)
template< class T > using remove_volatile_t = typename remove_volatile<T>::type;		(since C++14)

Possible implementation

template< class T > struct remove_cv { typedef typename std::remove_volatile<typename std::remove_const<T>::type>::type type; };   template< class T > struct remove_const { typedef T type; }; template< class T > struct remove_const<const T> { typedef T type; };   template< class T > struct remove_volatile { typedef T type; }; template< class T > struct remove_volatile<volatile T> { typedef T type; };