__cxx03/__algorithm/for_each.h

0001 // -*- C++ -*-
0002 //===----------------------------------------------------------------------===//
0003 //
0004 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0005 // See https://llvm.org/LICENSE.txt for license information.
0006 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0007 //
0008 //===----------------------------------------------------------------------===//
0009
0010 #ifndef _LIBCPP___CXX03___ALGORITHM_FOR_EACH_H
0011 #define _LIBCPP___CXX03___ALGORITHM_FOR_EACH_H
0012
0013 #include <__cxx03/__algorithm/for_each_segment.h>
0014 #include <__cxx03/__config>
0015 #include <__cxx03/__iterator/segmented_iterator.h>
0016 #include <__cxx03/__ranges/movable_box.h>
0017 #include <__cxx03/__type_traits/enable_if.h>
0018 #include <__cxx03/__utility/in_place.h>
0019 #include <__cxx03/__utility/move.h>
0020
0021 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0022 #  pragma GCC system_header
0023 #endif
0024
0025 _LIBCPP_PUSH_MACROS
0026 #include <__cxx03/__undef_macros>
0027
0028 _LIBCPP_BEGIN_NAMESPACE_STD
0029
0030 template <class _InputIterator, class _Function>
0031 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Function
0032 for_each(_InputIterator __first, _InputIterator __last, _Function __f) {
0033   for (; __first != __last; ++__first)
0034     __f(*__first);
0035   return __f;
0036 }
0037
0038 // __movable_box is available in C++20, but is actually a copyable-box, so optimization is only correct in C++23
0039 #if _LIBCPP_STD_VER >= 23
0040 template <class _SegmentedIterator, class _Function>
0041   requires __is_segmented_iterator<_SegmentedIterator>::value
0042 _LIBCPP_HIDE_FROM_ABI constexpr _Function
0043 for_each(_SegmentedIterator __first, _SegmentedIterator __last, _Function __func) {
0044   ranges::__movable_box<_Function> __wrapped_func(in_place, std::move(__func));
0045   std::__for_each_segment(__first, __last, [&](auto __lfirst, auto __llast) {
0046     __wrapped_func =
0047         ranges::__movable_box<_Function>(in_place, std::for_each(__lfirst, __llast, std::move(*__wrapped_func)));
0048   });
0049   return std::move(*__wrapped_func);
0050 }
0051 #endif // _LIBCPP_STD_VER >= 23
0052
0053 _LIBCPP_END_NAMESPACE_STD
0054
0055 _LIBCPP_POP_MACROS
0056
0057 #endif // _LIBCPP___CXX03___ALGORITHM_FOR_EACH_H