1e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===// 2e78f53d1SNikolas Klauser // 3e78f53d1SNikolas Klauser // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4e78f53d1SNikolas Klauser // See https://llvm.org/LICENSE.txt for license information. 5e78f53d1SNikolas Klauser // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6e78f53d1SNikolas Klauser // 7e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===// 8e78f53d1SNikolas Klauser 9*ce777190SNikolas Klauser #ifndef _LIBCPP___CXX03___COMPARE_PARTIAL_ORDER 10*ce777190SNikolas Klauser #define _LIBCPP___CXX03___COMPARE_PARTIAL_ORDER 11e78f53d1SNikolas Klauser 1273fbae83SNikolas Klauser #include <__cxx03/__compare/compare_three_way.h> 1373fbae83SNikolas Klauser #include <__cxx03/__compare/ordering.h> 1473fbae83SNikolas Klauser #include <__cxx03/__compare/weak_order.h> 1573fbae83SNikolas Klauser #include <__cxx03/__config> 1673fbae83SNikolas Klauser #include <__cxx03/__type_traits/decay.h> 1773fbae83SNikolas Klauser #include <__cxx03/__type_traits/is_same.h> 1873fbae83SNikolas Klauser #include <__cxx03/__utility/forward.h> 1973fbae83SNikolas Klauser #include <__cxx03/__utility/priority_tag.h> 20e78f53d1SNikolas Klauser 21e78f53d1SNikolas Klauser #ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER 22e78f53d1SNikolas Klauser # pragma GCC system_header 23e78f53d1SNikolas Klauser #endif 24e78f53d1SNikolas Klauser 25e78f53d1SNikolas Klauser _LIBCPP_BEGIN_NAMESPACE_STD 26e78f53d1SNikolas Klauser 27e78f53d1SNikolas Klauser #if _LIBCPP_STD_VER >= 20 28e78f53d1SNikolas Klauser 29e78f53d1SNikolas Klauser // [cmp.alg] 30e78f53d1SNikolas Klauser namespace __partial_order { 31e78f53d1SNikolas Klauser void partial_order() = delete; 32e78f53d1SNikolas Klauser 33e78f53d1SNikolas Klauser struct __fn { 34e78f53d1SNikolas Klauser // NOLINTBEGIN(libcpp-robust-against-adl) partial_order should use ADL, but only here 35e78f53d1SNikolas Klauser template <class _Tp, class _Up> 36e78f53d1SNikolas Klauser requires is_same_v<decay_t<_Tp>, decay_t<_Up>> 37e78f53d1SNikolas Klauser _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<2>) noexcept( 38e78f53d1SNikolas Klauser noexcept(partial_ordering(partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))))) 39e78f53d1SNikolas Klauser -> decltype(partial_ordering(partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) { 40e78f53d1SNikolas Klauser return partial_ordering(partial_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))); 41e78f53d1SNikolas Klauser } 42e78f53d1SNikolas Klauser // NOLINTEND(libcpp-robust-against-adl) 43e78f53d1SNikolas Klauser 44e78f53d1SNikolas Klauser template <class _Tp, class _Up> 45e78f53d1SNikolas Klauser requires is_same_v<decay_t<_Tp>, decay_t<_Up>> 46e78f53d1SNikolas Klauser _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<1>) noexcept( 47e78f53d1SNikolas Klauser noexcept(partial_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u))))) 48e78f53d1SNikolas Klauser -> decltype(partial_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) { 49e78f53d1SNikolas Klauser return partial_ordering(compare_three_way()(std::forward<_Tp>(__t), std::forward<_Up>(__u))); 50e78f53d1SNikolas Klauser } 51e78f53d1SNikolas Klauser 52e78f53d1SNikolas Klauser template <class _Tp, class _Up> 53e78f53d1SNikolas Klauser requires is_same_v<decay_t<_Tp>, decay_t<_Up>> 54e78f53d1SNikolas Klauser _LIBCPP_HIDE_FROM_ABI static constexpr auto __go(_Tp&& __t, _Up&& __u, __priority_tag<0>) noexcept( 55e78f53d1SNikolas Klauser noexcept(partial_ordering(std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))))) 56e78f53d1SNikolas Klauser -> decltype(partial_ordering(std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u)))) { 57e78f53d1SNikolas Klauser return partial_ordering(std::weak_order(std::forward<_Tp>(__t), std::forward<_Up>(__u))); 58e78f53d1SNikolas Klauser } 59e78f53d1SNikolas Klauser 60e78f53d1SNikolas Klauser template <class _Tp, class _Up> 61e78f53d1SNikolas Klauser _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t, _Up&& __u) const 62e78f53d1SNikolas Klauser noexcept(noexcept(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>()))) 63e78f53d1SNikolas Klauser -> decltype(__go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>())) { 64e78f53d1SNikolas Klauser return __go(std::forward<_Tp>(__t), std::forward<_Up>(__u), __priority_tag<2>()); 65e78f53d1SNikolas Klauser } 66e78f53d1SNikolas Klauser }; 67e78f53d1SNikolas Klauser } // namespace __partial_order 68e78f53d1SNikolas Klauser 69e78f53d1SNikolas Klauser inline namespace __cpo { 70e78f53d1SNikolas Klauser inline constexpr auto partial_order = __partial_order::__fn{}; 71e78f53d1SNikolas Klauser } // namespace __cpo 72e78f53d1SNikolas Klauser 73e78f53d1SNikolas Klauser #endif // _LIBCPP_STD_VER >= 20 74e78f53d1SNikolas Klauser 75e78f53d1SNikolas Klauser _LIBCPP_END_NAMESPACE_STD 76e78f53d1SNikolas Klauser 77*ce777190SNikolas Klauser #endif // _LIBCPP___CXX03___COMPARE_PARTIAL_ORDER 78