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_FOR_EACH_H
10 #define _LIBCPP___ALGORITHM_RANGES_FOR_EACH_H
11 
12 #include <__algorithm/in_fun_result.h>
13 #include <__config>
14 #include <__functional/identity.h>
15 #include <__functional/invoke.h>
16 #include <__iterator/concepts.h>
17 #include <__iterator/projected.h>
18 #include <__ranges/access.h>
19 #include <__ranges/concepts.h>
20 #include <__ranges/dangling.h>
21 #include <__utility/move.h>
22 
23 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
24 #  pragma GCC system_header
25 #endif
26 
27 #if _LIBCPP_STD_VER >= 20
28 
29 _LIBCPP_BEGIN_NAMESPACE_STD
30 
31 namespace ranges {
32 
33 template <class _Iter, class _Func>
34 using for_each_result = in_fun_result<_Iter, _Func>;
35 
36 namespace __for_each {
37 struct __fn {
38 private:
39   template <class _Iter, class _Sent, class _Proj, class _Func>
40   _LIBCPP_HIDE_FROM_ABI constexpr static for_each_result<_Iter, _Func>
41   __for_each_impl(_Iter __first, _Sent __last, _Func& __func, _Proj& __proj) {
42     for (; __first != __last; ++__first)
43       std::invoke(__func, std::invoke(__proj, *__first));
44     return {std::move(__first), std::move(__func)};
45   }
46 
47 public:
48   template <input_iterator _Iter,
49             sentinel_for<_Iter> _Sent,
50             class _Proj = identity,
51             indirectly_unary_invocable<projected<_Iter, _Proj>> _Func>
52   _LIBCPP_HIDE_FROM_ABI constexpr for_each_result<_Iter, _Func>
53   operator()(_Iter __first, _Sent __last, _Func __func, _Proj __proj = {}) const {
54     return __for_each_impl(std::move(__first), std::move(__last), __func, __proj);
55   }
56 
57   template <input_range _Range,
58             class _Proj = identity,
59             indirectly_unary_invocable<projected<iterator_t<_Range>, _Proj>> _Func>
60   _LIBCPP_HIDE_FROM_ABI constexpr for_each_result<borrowed_iterator_t<_Range>, _Func>
61   operator()(_Range&& __range, _Func __func, _Proj __proj = {}) const {
62     return __for_each_impl(ranges::begin(__range), ranges::end(__range), __func, __proj);
63   }
64 };
65 } // namespace __for_each
66 
67 inline namespace __cpo {
68 inline constexpr auto for_each = __for_each::__fn{};
69 } // namespace __cpo
70 } // namespace ranges
71 
72 _LIBCPP_END_NAMESPACE_STD
73 
74 #endif // _LIBCPP_STD_VER >= 20
75 
76 #endif // _LIBCPP___ALGORITHM_RANGES_FOR_EACH_H
77