1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
10 #define _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
11 
12 #include <__algorithm/ranges_min_element.h>
13 #include <__config>
14 #include <__functional/identity.h>
15 #include <__functional/invoke.h>
16 #include <__functional/ranges_operations.h>
17 #include <__iterator/concepts.h>
18 #include <__iterator/projected.h>
19 #include <__ranges/access.h>
20 #include <__ranges/concepts.h>
21 #include <__ranges/dangling.h>
22 
23 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
24 #  pragma GCC system_header
25 #endif
26 
27 #if _LIBCPP_STD_VER > 17
28 
29 _LIBCPP_BEGIN_NAMESPACE_STD
30 
31 namespace ranges {
32 namespace __max_element {
33 struct __fn {
34   template <forward_iterator _Ip, sentinel_for<_Ip> _Sp, class _Proj = identity,
35             indirect_strict_weak_order<projected<_Ip, _Proj>> _Comp = ranges::less>
36   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr
operator__fn37   _Ip operator()(_Ip __first, _Sp __last, _Comp __comp = {}, _Proj __proj = {}) const {
38     auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) { return std::invoke(__comp, __rhs, __lhs); };
39     return ranges::__min_element_impl(__first, __last, __comp_lhs_rhs_swapped, __proj);
40   }
41 
42   template <forward_range _Rp, class _Proj = identity,
43             indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
44   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr
operator__fn45   borrowed_iterator_t<_Rp> operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
46     auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) { return std::invoke(__comp, __rhs, __lhs); };
47     return ranges::__min_element_impl(ranges::begin(__r), ranges::end(__r), __comp_lhs_rhs_swapped, __proj);
48   }
49 };
50 } // namespace __max_element
51 
52 inline namespace __cpo {
53   inline constexpr auto max_element = __max_element::__fn{};
54 } // namespace __cpo
55 } // namespace ranges
56 
57 _LIBCPP_END_NAMESPACE_STD
58 
59 #endif // _LIBCPP_STD_VER > 17
60 
61 #endif // _LIBCPP___ALGORITHM_RANGES_MAX_ELEMENT_H
62