| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef _LIBCPP___TYPE_TRAITS_DECAY_H |
| #define _LIBCPP___TYPE_TRAITS_DECAY_H |
| |
| #include <__config> |
| #include <__type_traits/add_pointer.h> |
| #include <__type_traits/conditional.h> |
| #include <__type_traits/integral_constant.h> |
| #include <__type_traits/is_array.h> |
| #include <__type_traits/is_function.h> |
| #include <__type_traits/is_referenceable.h> |
| #include <__type_traits/remove_cv.h> |
| #include <__type_traits/remove_extent.h> |
| #include <__type_traits/remove_reference.h> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| # pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| template <class _Up, bool> |
| struct __decay { |
| typedef _LIBCPP_NODEBUG typename remove_cv<_Up>::type type; |
| }; |
| |
| template <class _Up> |
| struct __decay<_Up, true> { |
| public: |
| typedef _LIBCPP_NODEBUG typename conditional |
| < |
| is_array<_Up>::value, |
| typename remove_extent<_Up>::type*, |
| typename conditional |
| < |
| is_function<_Up>::value, |
| typename add_pointer<_Up>::type, |
| typename remove_cv<_Up>::type |
| >::type |
| >::type type; |
| }; |
| |
| template <class _Tp> |
| struct _LIBCPP_TEMPLATE_VIS decay |
| { |
| private: |
| typedef _LIBCPP_NODEBUG typename remove_reference<_Tp>::type _Up; |
| public: |
| typedef _LIBCPP_NODEBUG typename __decay<_Up, __is_referenceable<_Up>::value>::type type; |
| }; |
| |
| #if _LIBCPP_STD_VER > 11 |
| template <class _Tp> using decay_t = typename decay<_Tp>::type; |
| #endif |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP___TYPE_TRAITS_DECAY_H |
