1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___TYPE_TRAITS_COPY_CVREF_H 10 #define _LIBCPP___TYPE_TRAITS_COPY_CVREF_H 11 12 #include <__config> 13 #include <__type_traits/add_lvalue_reference.h> 14 #include <__type_traits/add_rvalue_reference.h> 15 #include <__type_traits/copy_cv.h> 16 17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 18 # pragma GCC system_header 19 #endif 20 21 _LIBCPP_BEGIN_NAMESPACE_STD 22 23 template <class _From> 24 struct __copy_cvref { 25 template <class _To> 26 using __apply _LIBCPP_NODEBUG = __copy_cv_t<_From, _To>; 27 }; 28 29 template <class _From> 30 struct __copy_cvref<_From&> { 31 template <class _To> 32 using __apply _LIBCPP_NODEBUG = __add_lvalue_reference_t<__copy_cv_t<_From, _To> >; 33 }; 34 35 template <class _From> 36 struct __copy_cvref<_From&&> { 37 template <class _To> 38 using __apply _LIBCPP_NODEBUG = __add_rvalue_reference_t<__copy_cv_t<_From, _To> >; 39 }; 40 41 template <class _From, class _To> 42 using __copy_cvref_t _LIBCPP_NODEBUG = typename __copy_cvref<_From>::template __apply<_To>; 43 44 _LIBCPP_END_NAMESPACE_STD 45 46 #endif // _LIBCPP___TYPE_TRAITS_COPY_CVREF_H 47