| //===----------------------------------------------------------------------===// |
| // |
| // 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___FUNCTIONAL_UNWRAP_REF_H |
| #define _LIBCPP___FUNCTIONAL_UNWRAP_REF_H |
| |
| #include <__config> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| #pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| template <class _Tp> |
| struct __unwrap_reference { typedef _LIBCPP_NODEBUG _Tp type; }; |
| |
| template <class _Tp> |
| class reference_wrapper; |
| |
| template <class _Tp> |
| struct __unwrap_reference<reference_wrapper<_Tp> > { typedef _LIBCPP_NODEBUG _Tp& type; }; |
| |
| template <class _Tp> |
| struct decay; |
| |
| #if _LIBCPP_STD_VER > 17 |
| template <class _Tp> |
| struct unwrap_reference : __unwrap_reference<_Tp> { }; |
| |
| template <class _Tp> |
| using unwrap_reference_t = typename unwrap_reference<_Tp>::type; |
| |
| template <class _Tp> |
| struct unwrap_ref_decay : unwrap_reference<typename decay<_Tp>::type> { }; |
| |
| template <class _Tp> |
| using unwrap_ref_decay_t = typename unwrap_ref_decay<_Tp>::type; |
| #endif // > C++17 |
| |
| template <class _Tp> |
| struct __unwrap_ref_decay |
| #if _LIBCPP_STD_VER > 17 |
| : unwrap_ref_decay<_Tp> |
| #else |
| : __unwrap_reference<typename decay<_Tp>::type> |
| #endif |
| { }; |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP___FUNCTIONAL_UNWRAP_REF_H |