v1/__concepts/relation.h

0001 //===----------------------------------------------------------------------===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008
0009 #ifndef _LIBCPP___CONCEPTS_RELATION_H
0010 #define _LIBCPP___CONCEPTS_RELATION_H
0011
0012 #include <__concepts/predicate.h>
0013 #include <__config>
0014
0015 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0016 #  pragma GCC system_header
0017 #endif
0018
0019 _LIBCPP_BEGIN_NAMESPACE_STD
0020
0021 #if _LIBCPP_STD_VER >= 20
0022
0023 // [concept.relation]
0024
0025 template <class _Rp, class _Tp, class _Up>
0026 concept relation =
0027     predicate<_Rp, _Tp, _Tp> && predicate<_Rp, _Up, _Up> && predicate<_Rp, _Tp, _Up> && predicate<_Rp, _Up, _Tp>;
0028
0029 // [concept.equiv]
0030
0031 template <class _Rp, class _Tp, class _Up>
0032 concept equivalence_relation = relation<_Rp, _Tp, _Up>;
0033
0034 // [concept.strictweakorder]
0035
0036 template <class _Rp, class _Tp, class _Up>
0037 concept strict_weak_order = relation<_Rp, _Tp, _Up>;
0038
0039 #endif // _LIBCPP_STD_VER >= 20
0040
0041 _LIBCPP_END_NAMESPACE_STD
0042
0043 #endif // _LIBCPP___CONCEPTS_RELATION_H