__cxx03/__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___CXX03___ALGORITHM_RANGES_MAX_ELEMENT_H
0010 #define _LIBCPP___CXX03___ALGORITHM_RANGES_MAX_ELEMENT_H
0011
0012 #include <__cxx03/__algorithm/ranges_min_element.h>
0013 #include <__cxx03/__config>
0014 #include <__cxx03/__functional/identity.h>
0015 #include <__cxx03/__functional/invoke.h>
0016 #include <__cxx03/__functional/ranges_operations.h>
0017 #include <__cxx03/__iterator/concepts.h>
0018 #include <__cxx03/__iterator/projected.h>
0019 #include <__cxx03/__ranges/access.h>
0020 #include <__cxx03/__ranges/concepts.h>
0021 #include <__cxx03/__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 <__cxx03/__undef_macros>
0029
0030 #if _LIBCPP_STD_VER >= 20
0031
0032 _LIBCPP_BEGIN_NAMESPACE_STD
0033
0034 namespace ranges {
0035 namespace __max_element {
0036 struct __fn {
0037   template <forward_iterator _Ip,
0038             sentinel_for<_Ip> _Sp,
0039             class _Proj                                             = identity,
0040             indirect_strict_weak_order<projected<_Ip, _Proj>> _Comp = ranges::less>
0041   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Ip
0042   operator()(_Ip __first, _Sp __last, _Comp __comp = {}, _Proj __proj = {}) const {
0043     auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
0044     return ranges::__min_element_impl(__first, __last, __comp_lhs_rhs_swapped, __proj);
0045   }
0046
0047   template <forward_range _Rp,
0048             class _Proj                                                         = identity,
0049             indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
0050   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp>
0051   operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
0052     auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
0053     return ranges::__min_element_impl(ranges::begin(__r), ranges::end(__r), __comp_lhs_rhs_swapped, __proj);
0054   }
0055 };
0056 } // namespace __max_element
0057
0058 inline namespace __cpo {
0059 inline constexpr auto max_element = __max_element::__fn{};
0060 } // namespace __cpo
0061 } // namespace ranges
0062
0063 _LIBCPP_END_NAMESPACE_STD
0064
0065 #endif // _LIBCPP_STD_VER >= 20
0066
0067 _LIBCPP_POP_MACROS
0068
0069 #endif // _LIBCPP___CXX03___ALGORITHM_RANGES_MAX_ELEMENT_H