1349cc55cSDimitry Andric //===----------------------------------------------------------------------===// 2349cc55cSDimitry Andric // 3349cc55cSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4349cc55cSDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 5349cc55cSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6349cc55cSDimitry Andric // 7349cc55cSDimitry Andric //===----------------------------------------------------------------------===// 8349cc55cSDimitry Andric 9349cc55cSDimitry Andric #ifndef _LIBCPP___COMPARE_THREE_WAY_COMPARABLE_H 10349cc55cSDimitry Andric #define _LIBCPP___COMPARE_THREE_WAY_COMPARABLE_H 11349cc55cSDimitry Andric 12349cc55cSDimitry Andric #include <__compare/common_comparison_category.h> 13349cc55cSDimitry Andric #include <__compare/ordering.h> 14349cc55cSDimitry Andric #include <__concepts/common_reference_with.h> 15349cc55cSDimitry Andric #include <__concepts/equality_comparable.h> 16349cc55cSDimitry Andric #include <__concepts/same_as.h> 17349cc55cSDimitry Andric #include <__concepts/totally_ordered.h> 18349cc55cSDimitry Andric #include <__config> 19bdd1243dSDimitry Andric #include <__type_traits/common_reference.h> 20bdd1243dSDimitry Andric #include <__type_traits/make_const_lvalue_ref.h> 21349cc55cSDimitry Andric 22349cc55cSDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 23349cc55cSDimitry Andric # pragma GCC system_header 24349cc55cSDimitry Andric #endif 25349cc55cSDimitry Andric 26349cc55cSDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 27349cc55cSDimitry Andric 2806c3fb27SDimitry Andric #if _LIBCPP_STD_VER >= 20 29349cc55cSDimitry Andric 30349cc55cSDimitry Andric template <class _Tp, class _Cat> 31*cb14a3feSDimitry Andric concept __compares_as = same_as<common_comparison_category_t<_Tp, _Cat>, _Cat>; 32349cc55cSDimitry Andric 33349cc55cSDimitry Andric template <class _Tp, class _Cat = partial_ordering> 34349cc55cSDimitry Andric concept three_way_comparable = 35*cb14a3feSDimitry Andric __weakly_equality_comparable_with<_Tp, _Tp> && __partially_ordered_with<_Tp, _Tp> && requires(__make_const_lvalue_ref<_Tp> __a,__make_const_lvalue_ref<_Tp> __b)36349cc55cSDimitry Andric requires(__make_const_lvalue_ref<_Tp> __a, __make_const_lvalue_ref<_Tp> __b) { 37349cc55cSDimitry Andric { __a <=> __b } -> __compares_as<_Cat>; 38349cc55cSDimitry Andric }; 39349cc55cSDimitry Andric 40349cc55cSDimitry Andric template <class _Tp, class _Up, class _Cat = partial_ordering> 41349cc55cSDimitry Andric concept three_way_comparable_with = 42*cb14a3feSDimitry Andric three_way_comparable<_Tp, _Cat> && three_way_comparable<_Up, _Cat> && 43349cc55cSDimitry Andric common_reference_with<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>> && 44349cc55cSDimitry Andric three_way_comparable<common_reference_t<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>>, _Cat> && 45*cb14a3feSDimitry Andric __weakly_equality_comparable_with<_Tp, _Up> && __partially_ordered_with<_Tp, _Up> && requires(__make_const_lvalue_ref<_Tp> __t,__make_const_lvalue_ref<_Up> __u)46349cc55cSDimitry Andric requires(__make_const_lvalue_ref<_Tp> __t, __make_const_lvalue_ref<_Up> __u) { 47349cc55cSDimitry Andric { __t <=> __u } -> __compares_as<_Cat>; 48349cc55cSDimitry Andric { __u <=> __t } -> __compares_as<_Cat>; 49349cc55cSDimitry Andric }; 50349cc55cSDimitry Andric 5106c3fb27SDimitry Andric #endif // _LIBCPP_STD_VER >= 20 52349cc55cSDimitry Andric 53349cc55cSDimitry Andric _LIBCPP_END_NAMESPACE_STD 54349cc55cSDimitry Andric 55349cc55cSDimitry Andric #endif // _LIBCPP___COMPARE_THREE_WAY_COMPARABLE_H 56