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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___CONCEPTS_ASSIGNABLE_H
#define _LIBCPP___CONCEPTS_ASSIGNABLE_H
#include <__concepts/common_reference_with.h>
#include <__concepts/same_as.h>
#include <__config>
#include <__utility/forward.h>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CONCEPTS)
// [concept.assignable]
template<class _Lhs, class _Rhs>
concept assignable_from =
is_lvalue_reference_v<_Lhs> &&
common_reference_with<__make_const_lvalue_ref<_Lhs>, __make_const_lvalue_ref<_Rhs>> &&
requires (_Lhs __lhs, _Rhs&& __rhs) {
{ __lhs = _VSTD::forward<_Rhs>(__rhs) } -> same_as<_Lhs>;
};
#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CONCEPTS)
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___CONCEPTS_ASSIGNABLE_H