reduce.h 1.7 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748
  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. #ifndef _LIBCPP___NUMERIC_REDUCE_H
  10. #define _LIBCPP___NUMERIC_REDUCE_H
  11. #include <__config>
  12. #include <__functional/operations.h>
  13. #include <__iterator/iterator_traits.h>
  14. #include <__utility/move.h>
  15. #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  16. # pragma GCC system_header
  17. #endif
  18. _LIBCPP_BEGIN_NAMESPACE_STD
  19. #if _LIBCPP_STD_VER >= 17
  20. template <class _InputIterator, class _Tp, class _BinaryOp>
  21. _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp reduce(_InputIterator __first, _InputIterator __last,
  22. _Tp __init, _BinaryOp __b) {
  23. for (; __first != __last; ++__first)
  24. __init = __b(std::move(__init), *__first);
  25. return __init;
  26. }
  27. template <class _InputIterator, class _Tp>
  28. _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp reduce(_InputIterator __first, _InputIterator __last,
  29. _Tp __init) {
  30. return _VSTD::reduce(__first, __last, __init, _VSTD::plus<>());
  31. }
  32. template <class _InputIterator>
  33. _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 typename iterator_traits<_InputIterator>::value_type
  34. reduce(_InputIterator __first, _InputIterator __last) {
  35. return _VSTD::reduce(__first, __last, typename iterator_traits<_InputIterator>::value_type{});
  36. }
  37. #endif
  38. _LIBCPP_END_NAMESPACE_STD
  39. #endif // _LIBCPP___NUMERIC_REDUCE_H