libcxx/include/__algorithm/for_each.h

   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