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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_REFERENCE_WITH_H10#define _LIBCPP___CONCEPTS_COMMON_REFERENCE_WITH_H11 12#include <__concepts/convertible_to.h>13#include <__concepts/same_as.h>14#include <__config>15#include <__type_traits/common_reference.h>16 17#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)18# pragma GCC system_header19#endif20 21_LIBCPP_BEGIN_NAMESPACE_STD22 23#if _LIBCPP_STD_VER >= 2024 25// [concept.commonref]26 27template <class _Tp, class _Up>28concept common_reference_with =29 same_as<common_reference_t<_Tp, _Up>, common_reference_t<_Up, _Tp>> &&30 convertible_to<_Tp, common_reference_t<_Tp, _Up>> && convertible_to<_Up, common_reference_t<_Tp, _Up>>;31 32#endif // _LIBCPP_STD_VER >= 2033 34_LIBCPP_END_NAMESPACE_STD35 36#endif // _LIBCPP___CONCEPTS_COMMON_REFERENCE_WITH_H37