1 // -*- C++ -*- 2 //===----------------------------------------------------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef _LIBCPP___UTILITY_FORWARD_H 11 #define _LIBCPP___UTILITY_FORWARD_H 12 13 #include <__config> 14 #include <type_traits> 15 16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 17 #pragma GCC system_header 18 #endif 19 20 _LIBCPP_PUSH_MACROS 21 #include <__undef_macros> 22 23 _LIBCPP_BEGIN_NAMESPACE_STD 24 25 template <class _Tp> 26 _LIBCPP_NODISCARD_EXT inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR _Tp&& 27 forward(typename remove_reference<_Tp>::type& __t) _NOEXCEPT { 28 return static_cast<_Tp&&>(__t); 29 } 30 31 template <class _Tp> 32 _LIBCPP_NODISCARD_EXT inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR _Tp&& 33 forward(typename remove_reference<_Tp>::type&& __t) _NOEXCEPT { 34 static_assert(!is_lvalue_reference<_Tp>::value, "cannot forward an rvalue as an lvalue"); 35 return static_cast<_Tp&&>(__t); 36 } 37 38 _LIBCPP_END_NAMESPACE_STD 39 40 _LIBCPP_POP_MACROS 41 42 #endif // _LIBCPP___UTILITY_FORWARD_H 43