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_MOVE_H 11 #define _LIBCPP___UTILITY_MOVE_H 12 13 #include <__config> 14 #include <__type_traits/conditional.h> 15 #include <__type_traits/is_copy_constructible.h> 16 #include <__type_traits/is_nothrow_move_constructible.h> 17 #include <__type_traits/remove_reference.h> 18 19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 20 # pragma GCC system_header 21 #endif 22 23 _LIBCPP_PUSH_MACROS 24 #include <__undef_macros> 25 26 _LIBCPP_BEGIN_NAMESPACE_STD 27 28 template <class _Tp> 29 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __libcpp_remove_reference_t<_Tp>&& 30 move(_LIBCPP_LIFETIMEBOUND _Tp&& __t) _NOEXCEPT { 31 typedef _LIBCPP_NODEBUG __libcpp_remove_reference_t<_Tp> _Up; 32 return static_cast<_Up&&>(__t); 33 } 34 35 template <class _Tp> 36 using __move_if_noexcept_result_t = 37 __conditional_t<!is_nothrow_move_constructible<_Tp>::value && is_copy_constructible<_Tp>::value, const _Tp&, _Tp&&>; 38 39 template <class _Tp> 40 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __move_if_noexcept_result_t<_Tp> 41 move_if_noexcept(_LIBCPP_LIFETIMEBOUND _Tp& __x) _NOEXCEPT { 42 return std::move(__x); 43 } 44 45 _LIBCPP_END_NAMESPACE_STD 46 47 _LIBCPP_POP_MACROS 48 49 #endif // _LIBCPP___UTILITY_MOVE_H 50