v1/__algorithm/ranges_max_element.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___ALGORITHM_RANGES_MAX_ELEMENT_H
0010 #define _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
0011
0012 #include <__algorithm/ranges_min_element.h>
0013 #include <__config>
0014 #include <__functional/identity.h>
0015 #include <__functional/invoke.h>
0016 #include <__functional/ranges_operations.h>
0017 #include <__iterator/concepts.h>
0018 #include <__iterator/projected.h>
0019 #include <__ranges/access.h>
0020 #include <__ranges/concepts.h>
0021 #include <__ranges/dangling.h>
0022
0023 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0024 #  pragma GCC system_header
0025 #endif
0026
0027 _LIBCPP_PUSH_MACROS
0028 #include <__undef_macros>
0029
0030 #if _LIBCPP_STD_VER >= 20
0031
0032 _LIBCPP_BEGIN_NAMESPACE_STD
0033
0034 namespace ranges {
0035 struct __max_element {
0036   template <forward_iterator _Ip,
0037             sentinel_for<_Ip> _Sp,
0038             class _Proj                                             = identity,
0039             indirect_strict_weak_order<projected<_Ip, _Proj>> _Comp = ranges::less>
0040   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Ip
0041   operator()(_Ip __first, _Sp __last, _Comp __comp = {}, _Proj __proj = {}) const {
0042     auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
0043     return ranges::__min_element_impl(__first, __last, __comp_lhs_rhs_swapped, __proj);
0044   }
0045
0046   template <forward_range _Rp,
0047             class _Proj                                                         = identity,
0048             indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
0049   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp>
0050   operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
0051     auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
0052     return ranges::__min_element_impl(ranges::begin(__r), ranges::end(__r), __comp_lhs_rhs_swapped, __proj);
0053   }
0054 };
0055
0056 inline namespace __cpo {
0057 inline constexpr auto max_element = __max_element{};
0058 } // namespace __cpo
0059 } // namespace ranges
0060
0061 _LIBCPP_END_NAMESPACE_STD
0062
0063 #endif // _LIBCPP_STD_VER >= 20
0064
0065 _LIBCPP_POP_MACROS
0066
0067 #endif // _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H