xref: /llvm-project/libcxx/include/__algorithm/ranges_max_element.h (revision d10dc5a06fac4dcabf2264c64c8672c6f6ae36fb)
1205557c9SNikolas Klauser //===----------------------------------------------------------------------===//
2205557c9SNikolas Klauser //
3205557c9SNikolas Klauser // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4205557c9SNikolas Klauser // See https://llvm.org/LICENSE.txt for license information.
5205557c9SNikolas Klauser // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6205557c9SNikolas Klauser //
7205557c9SNikolas Klauser //===----------------------------------------------------------------------===//
8205557c9SNikolas Klauser 
9205557c9SNikolas Klauser #ifndef _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
10205557c9SNikolas Klauser #define _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
11205557c9SNikolas Klauser 
12e476df56SNikolas Klauser #include <__algorithm/ranges_min_element.h>
13205557c9SNikolas Klauser #include <__config>
14205557c9SNikolas Klauser #include <__functional/identity.h>
15205557c9SNikolas Klauser #include <__functional/invoke.h>
16205557c9SNikolas Klauser #include <__functional/ranges_operations.h>
17205557c9SNikolas Klauser #include <__iterator/concepts.h>
18205557c9SNikolas Klauser #include <__iterator/projected.h>
19205557c9SNikolas Klauser #include <__ranges/access.h>
20205557c9SNikolas Klauser #include <__ranges/concepts.h>
21205557c9SNikolas Klauser #include <__ranges/dangling.h>
22205557c9SNikolas Klauser 
23205557c9SNikolas Klauser #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
24205557c9SNikolas Klauser #  pragma GCC system_header
25205557c9SNikolas Klauser #endif
26205557c9SNikolas Klauser 
277b462251SLouis Dionne _LIBCPP_PUSH_MACROS
287b462251SLouis Dionne #include <__undef_macros>
297b462251SLouis Dionne 
304f15267dSNikolas Klauser #if _LIBCPP_STD_VER >= 20
31205557c9SNikolas Klauser 
32205557c9SNikolas Klauser _LIBCPP_BEGIN_NAMESPACE_STD
33205557c9SNikolas Klauser 
34205557c9SNikolas Klauser namespace ranges {
35*d10dc5a0SChristopher Di Bella struct __max_element {
365aa03b64SLouis Dionne   template <forward_iterator _Ip,
375aa03b64SLouis Dionne             sentinel_for<_Ip> _Sp,
385aa03b64SLouis Dionne             class _Proj                                             = identity,
39205557c9SNikolas Klauser             indirect_strict_weak_order<projected<_Ip, _Proj>> _Comp = ranges::less>
4083bc7b57SNikolas Klauser   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Ip
415aa03b64SLouis Dionne   operator()(_Ip __first, _Sp __last, _Comp __comp = {}, _Proj __proj = {}) const {
4202540b2fSLouis Dionne     auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
4340f7fca3SNikolas Klauser     return ranges::__min_element_impl(__first, __last, __comp_lhs_rhs_swapped, __proj);
44205557c9SNikolas Klauser   }
45205557c9SNikolas Klauser 
465aa03b64SLouis Dionne   template <forward_range _Rp,
475aa03b64SLouis Dionne             class _Proj                                                         = identity,
48205557c9SNikolas Klauser             indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
4983bc7b57SNikolas Klauser   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp>
505aa03b64SLouis Dionne   operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
5102540b2fSLouis Dionne     auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) -> bool { return std::invoke(__comp, __rhs, __lhs); };
5240f7fca3SNikolas Klauser     return ranges::__min_element_impl(ranges::begin(__r), ranges::end(__r), __comp_lhs_rhs_swapped, __proj);
53205557c9SNikolas Klauser   }
54205557c9SNikolas Klauser };
55205557c9SNikolas Klauser 
56205557c9SNikolas Klauser inline namespace __cpo {
57*d10dc5a0SChristopher Di Bella inline constexpr auto max_element = __max_element{};
58205557c9SNikolas Klauser } // namespace __cpo
59205557c9SNikolas Klauser } // namespace ranges
60205557c9SNikolas Klauser 
61205557c9SNikolas Klauser _LIBCPP_END_NAMESPACE_STD
62205557c9SNikolas Klauser 
634f15267dSNikolas Klauser #endif // _LIBCPP_STD_VER >= 20
64205557c9SNikolas Klauser 
657b462251SLouis Dionne _LIBCPP_POP_MACROS
667b462251SLouis Dionne 
67205557c9SNikolas Klauser #endif // _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
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