1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // <numeric>
10 // UNSUPPORTED: clang-8
11 
12 // Became constexpr in C++20
13 // template <InputIterator InIter, OutputIterator<auto, const InIter::value_type&> OutIter>
14 //   requires HasPlus<InIter::value_type, InIter::reference>
15 //         && HasAssign<InIter::value_type,
16 //                      HasPlus<InIter::value_type, InIter::reference>::result_type>
17 //         && Constructible<InIter::value_type, InIter::reference>
18 //   OutIter
19 //   partial_sum(InIter first, InIter last, OutIter result);
20 
21 #include <numeric>
22 #include <cassert>
23 
24 #include "test_macros.h"
25 #include "test_iterators.h"
26 
27 template <class InIter, class OutIter>
28 TEST_CONSTEXPR_CXX20 void
29 test()
30 {
31     int ia[] = {1, 2, 3, 4, 5};
32     int ir[] = {1, 3, 6, 10, 15};
33     const unsigned s = sizeof(ia) / sizeof(ia[0]);
34     int ib[s] = {0};
35     OutIter r = std::partial_sum(InIter(ia), InIter(ia+s), OutIter(ib));
36     assert(base(r) == ib + s);
37     for (unsigned i = 0; i < s; ++i)
38         assert(ib[i] == ir[i]);
39 }
40 
41 TEST_CONSTEXPR_CXX20 bool
42 test()
43 {
44     test<cpp17_input_iterator<const int*>, output_iterator<int*> >();
45     test<cpp17_input_iterator<const int*>, forward_iterator<int*> >();
46     test<cpp17_input_iterator<const int*>, bidirectional_iterator<int*> >();
47     test<cpp17_input_iterator<const int*>, random_access_iterator<int*> >();
48     test<cpp17_input_iterator<const int*>, int*>();
49 
50     test<forward_iterator<const int*>, output_iterator<int*> >();
51     test<forward_iterator<const int*>, forward_iterator<int*> >();
52     test<forward_iterator<const int*>, bidirectional_iterator<int*> >();
53     test<forward_iterator<const int*>, random_access_iterator<int*> >();
54     test<forward_iterator<const int*>, int*>();
55 
56     test<bidirectional_iterator<const int*>, output_iterator<int*> >();
57     test<bidirectional_iterator<const int*>, forward_iterator<int*> >();
58     test<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
59     test<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
60     test<bidirectional_iterator<const int*>, int*>();
61 
62     test<random_access_iterator<const int*>, output_iterator<int*> >();
63     test<random_access_iterator<const int*>, forward_iterator<int*> >();
64     test<random_access_iterator<const int*>, bidirectional_iterator<int*> >();
65     test<random_access_iterator<const int*>, random_access_iterator<int*> >();
66     test<random_access_iterator<const int*>, int*>();
67 
68     test<const int*, output_iterator<int*> >();
69     test<const int*, forward_iterator<int*> >();
70     test<const int*, bidirectional_iterator<int*> >();
71     test<const int*, random_access_iterator<int*> >();
72     test<const int*, int*>();
73 
74     return true;
75 }
76 
77 int main(int, char**)
78 {
79     test();
80 #if TEST_STD_VER > 17
81     static_assert(test());
82 #endif
83     return 0;
84 }
85