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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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___CONCEPTS_COMMON_WITH_H10#define _LIBCPP___CONCEPTS_COMMON_WITH_H11 12#include <__concepts/common_reference_with.h>13#include <__concepts/same_as.h>14#include <__config>15#include <__type_traits/add_reference.h>16#include <__type_traits/common_reference.h>17#include <__type_traits/common_type.h>18#include <__utility/declval.h>19 20#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)21# pragma GCC system_header22#endif23 24_LIBCPP_BEGIN_NAMESPACE_STD25 26#if _LIBCPP_STD_VER >= 2027 28// [concept.common]29 30// clang-format off31template <class _Tp, class _Up>32concept common_with =33 same_as<common_type_t<_Tp, _Up>, common_type_t<_Up, _Tp>> &&34 requires {35 static_cast<common_type_t<_Tp, _Up>>(std::declval<_Tp>());36 static_cast<common_type_t<_Tp, _Up>>(std::declval<_Up>());37 } &&38 common_reference_with<39 add_lvalue_reference_t<const _Tp>,40 add_lvalue_reference_t<const _Up>> &&41 common_reference_with<42 add_lvalue_reference_t<common_type_t<_Tp, _Up>>,43 common_reference_t<44 add_lvalue_reference_t<const _Tp>,45 add_lvalue_reference_t<const _Up>>>;46// clang-format on47 48#endif // _LIBCPP_STD_VER >= 2049 50_LIBCPP_END_NAMESPACE_STD51 52#endif // _LIBCPP___CONCEPTS_COMMON_WITH_H53