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___ITERATOR_MOVE_SENTINEL_H 10 #define _LIBCPP___ITERATOR_MOVE_SENTINEL_H 11 12 #include <__concepts/assignable.h> 13 #include <__concepts/convertible_to.h> 14 #include <__concepts/semiregular.h> 15 #include <__config> 16 #include <__utility/move.h> 17 18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 19 # pragma GCC system_header 20 #endif 21 22 _LIBCPP_PUSH_MACROS 23 #include <__undef_macros> 24 25 _LIBCPP_BEGIN_NAMESPACE_STD 26 27 #if _LIBCPP_STD_VER >= 20 28 29 template <semiregular _Sent> 30 class _LIBCPP_TEMPLATE_VIS move_sentinel 31 { 32 public: 33 _LIBCPP_HIDE_FROM_ABI 34 move_sentinel() = default; 35 36 _LIBCPP_HIDE_FROM_ABI constexpr 37 explicit move_sentinel(_Sent __s) : __last_(std::move(__s)) {} 38 39 template <class _S2> 40 requires convertible_to<const _S2&, _Sent> 41 _LIBCPP_HIDE_FROM_ABI constexpr 42 move_sentinel(const move_sentinel<_S2>& __s) : __last_(__s.base()) {} 43 44 template <class _S2> 45 requires assignable_from<_Sent&, const _S2&> 46 _LIBCPP_HIDE_FROM_ABI constexpr 47 move_sentinel& operator=(const move_sentinel<_S2>& __s) 48 { __last_ = __s.base(); return *this; } 49 50 _LIBCPP_HIDE_FROM_ABI constexpr _Sent base() const { return __last_; } 51 52 private: 53 _Sent __last_ = _Sent(); 54 }; 55 56 _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(move_sentinel); 57 58 #endif // _LIBCPP_STD_VER >= 20 59 60 _LIBCPP_END_NAMESPACE_STD 61 62 _LIBCPP_POP_MACROS 63 64 #endif // _LIBCPP___ITERATOR_MOVE_SENTINEL_H 65