xref: /llvm-project/libcxx/include/__algorithm/for_each.h (revision b905bcc5090cde734e8b7bbceae13bd5a606cc14)
1 // -*- C++ -*-
2 //===----------------------------------------------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef _LIBCPP___ALGORITHM_FOR_EACH_H
11 #define _LIBCPP___ALGORITHM_FOR_EACH_H
12 
13 #include <__algorithm/for_each_segment.h>
14 #include <__config>
15 #include <__iterator/segmented_iterator.h>
16 #include <__ranges/movable_box.h>
17 #include <__utility/in_place.h>
18 #include <__utility/move.h>
19 
20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
21 #  pragma GCC system_header
22 #endif
23 
24 _LIBCPP_PUSH_MACROS
25 #include <__undef_macros>
26 
27 _LIBCPP_BEGIN_NAMESPACE_STD
28 
29 template <class _InputIterator, class _Function>
30 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Function
31 for_each(_InputIterator __first, _InputIterator __last, _Function __f) {
32   for (; __first != __last; ++__first)
33     __f(*__first);
34   return __f;
35 }
36 
37 // __movable_box is available in C++20, but is actually a copyable-box, so optimization is only correct in C++23
38 #if _LIBCPP_STD_VER >= 23
39 template <class _SegmentedIterator, class _Function>
40   requires __is_segmented_iterator<_SegmentedIterator>::value
41 _LIBCPP_HIDE_FROM_ABI constexpr _Function
42 for_each(_SegmentedIterator __first, _SegmentedIterator __last, _Function __func) {
43   ranges::__movable_box<_Function> __wrapped_func(in_place, std::move(__func));
44   std::__for_each_segment(__first, __last, [&](auto __lfirst, auto __llast) {
45     __wrapped_func =
46         ranges::__movable_box<_Function>(in_place, std::for_each(__lfirst, __llast, std::move(*__wrapped_func)));
47   });
48   return std::move(*__wrapped_func);
49 }
50 #endif // _LIBCPP_STD_VER >= 23
51 
52 _LIBCPP_END_NAMESPACE_STD
53 
54 _LIBCPP_POP_MACROS
55 
56 #endif // _LIBCPP___ALGORITHM_FOR_EACH_H
57