xref: /freebsd/contrib/llvm-project/libcxx/include/__numeric/transform_reduce.h (revision 1db9f3b21e39176dd5b67cf8ac378633b172463e)
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___NUMERIC_TRANSFORM_REDUCE_H
11 #define _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
12 
13 #include <__config>
14 #include <__functional/operations.h>
15 #include <__utility/move.h>
16 
17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18 #  pragma GCC system_header
19 #endif
20 
21 _LIBCPP_BEGIN_NAMESPACE_STD
22 
23 #if _LIBCPP_STD_VER >= 17
24 template <class _InputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
25 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
26 transform_reduce(_InputIterator __first, _InputIterator __last, _Tp __init, _BinaryOp __b, _UnaryOp __u) {
27   for (; __first != __last; ++__first)
28     __init = __b(std::move(__init), __u(*__first));
29   return __init;
30 }
31 
32 template <class _InputIterator1, class _InputIterator2, class _Tp, class _BinaryOp1, class _BinaryOp2>
33 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp transform_reduce(
34     _InputIterator1 __first1,
35     _InputIterator1 __last1,
36     _InputIterator2 __first2,
37     _Tp __init,
38     _BinaryOp1 __b1,
39     _BinaryOp2 __b2) {
40   for (; __first1 != __last1; ++__first1, (void)++__first2)
41     __init = __b1(std::move(__init), __b2(*__first1, *__first2));
42   return __init;
43 }
44 
45 template <class _InputIterator1, class _InputIterator2, class _Tp>
46 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
47 transform_reduce(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _Tp __init) {
48   return std::transform_reduce(__first1, __last1, __first2, std::move(__init), std::plus<>(), std::multiplies<>());
49 }
50 #endif
51 
52 _LIBCPP_END_NAMESPACE_STD
53 
54 #endif // _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
55