xref: /freebsd/contrib/llvm-project/libcxx/include/__numeric/transform_reduce.h (revision 96190b4fef3b4a0cc3ca0606b0c4e3e69a5e6717)
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_PUSH_MACROS
22 #include <__undef_macros>
23 
24 _LIBCPP_BEGIN_NAMESPACE_STD
25 
26 #if _LIBCPP_STD_VER >= 17
27 template <class _InputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
28 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
29 transform_reduce(_InputIterator __first, _InputIterator __last, _Tp __init, _BinaryOp __b, _UnaryOp __u) {
30   for (; __first != __last; ++__first)
31     __init = __b(std::move(__init), __u(*__first));
32   return __init;
33 }
34 
35 template <class _InputIterator1, class _InputIterator2, class _Tp, class _BinaryOp1, class _BinaryOp2>
36 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp transform_reduce(
37     _InputIterator1 __first1,
38     _InputIterator1 __last1,
39     _InputIterator2 __first2,
40     _Tp __init,
41     _BinaryOp1 __b1,
42     _BinaryOp2 __b2) {
43   for (; __first1 != __last1; ++__first1, (void)++__first2)
44     __init = __b1(std::move(__init), __b2(*__first1, *__first2));
45   return __init;
46 }
47 
48 template <class _InputIterator1, class _InputIterator2, class _Tp>
49 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
50 transform_reduce(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _Tp __init) {
51   return std::transform_reduce(__first1, __last1, __first2, std::move(__init), std::plus<>(), std::multiplies<>());
52 }
53 #endif
54 
55 _LIBCPP_END_NAMESPACE_STD
56 
57 _LIBCPP_POP_MACROS
58 
59 #endif // _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
60