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
11 // Became constexpr in C++20
12 // template <InputIterator InIter,
13 // OutputIterator<auto, const InIter::value_type&> OutIter>
14 // requires HasMinus<InIter::value_type, InIter::value_type>
15 // && Constructible<InIter::value_type, InIter::reference>
16 // && OutputIterator<OutIter,
17 // HasMinus<InIter::value_type, InIter::value_type>::result_type>
18 // && MoveAssignable<InIter::value_type>
19 // OutIter
20 // adjacent_difference(InIter first, InIter last, OutIter result);
21
22 #include <numeric>
23 #include <cassert>
24
25 #include "test_macros.h"
26 #include "test_iterators.h"
27
28 template <class InIter, class OutIter>
29 TEST_CONSTEXPR_CXX20 void
test()30 test()
31 {
32 int ia[] = {15, 10, 6, 3, 1};
33 int ir[] = {15, -5, -4, -3, -2};
34 const unsigned s = sizeof(ia) / sizeof(ia[0]);
35 int ib[s] = {0};
36 OutIter r = std::adjacent_difference(InIter(ia), InIter(ia+s), OutIter(ib));
37 assert(base(r) == ib + s);
38 for (unsigned i = 0; i < s; ++i)
39 assert(ib[i] == ir[i]);
40 }
41
42 #if TEST_STD_VER >= 11
43
44 class Y;
45
46 class X
47 {
48 int i_;
49
50 TEST_CONSTEXPR_CXX20 X& operator=(const X&);
51 public:
X(int i)52 TEST_CONSTEXPR_CXX20 explicit X(int i) : i_(i) {}
X(const X & x)53 TEST_CONSTEXPR_CXX20 X(const X& x) : i_(x.i_) {}
operator =(X && x)54 TEST_CONSTEXPR_CXX20 X& operator=(X&& x)
55 {
56 i_ = x.i_;
57 x.i_ = -1;
58 return *this;
59 }
60
operator -(const X & x,const X & y)61 TEST_CONSTEXPR_CXX20 friend X operator-(const X& x, const X& y) {return X(x.i_ - y.i_);}
62
63 friend class Y;
64 };
65
66 class Y
67 {
68 int i_;
69
70 TEST_CONSTEXPR_CXX20 Y& operator=(const Y&);
71 public:
Y(int i)72 TEST_CONSTEXPR_CXX20 explicit Y(int i) : i_(i) {}
Y(const Y & y)73 TEST_CONSTEXPR_CXX20 Y(const Y& y) : i_(y.i_) {}
operator =(const X & x)74 TEST_CONSTEXPR_CXX20 void operator=(const X& x) {i_ = x.i_;}
75 };
76
77 #endif
78
79 TEST_CONSTEXPR_CXX20 bool
test()80 test()
81 {
82 test<cpp17_input_iterator<const int*>, cpp17_output_iterator<int*> >();
83 test<cpp17_input_iterator<const int*>, forward_iterator<int*> >();
84 test<cpp17_input_iterator<const int*>, bidirectional_iterator<int*> >();
85 test<cpp17_input_iterator<const int*>, random_access_iterator<int*> >();
86 test<cpp17_input_iterator<const int*>, int*>();
87
88 test<forward_iterator<const int*>, cpp17_output_iterator<int*> >();
89 test<forward_iterator<const int*>, forward_iterator<int*> >();
90 test<forward_iterator<const int*>, bidirectional_iterator<int*> >();
91 test<forward_iterator<const int*>, random_access_iterator<int*> >();
92 test<forward_iterator<const int*>, int*>();
93
94 test<bidirectional_iterator<const int*>, cpp17_output_iterator<int*> >();
95 test<bidirectional_iterator<const int*>, forward_iterator<int*> >();
96 test<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
97 test<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
98 test<bidirectional_iterator<const int*>, int*>();
99
100 test<random_access_iterator<const int*>, cpp17_output_iterator<int*> >();
101 test<random_access_iterator<const int*>, forward_iterator<int*> >();
102 test<random_access_iterator<const int*>, bidirectional_iterator<int*> >();
103 test<random_access_iterator<const int*>, random_access_iterator<int*> >();
104 test<random_access_iterator<const int*>, int*>();
105
106 test<const int*, cpp17_output_iterator<int*> >();
107 test<const int*, forward_iterator<int*> >();
108 test<const int*, bidirectional_iterator<int*> >();
109 test<const int*, random_access_iterator<int*> >();
110 test<const int*, int*>();
111
112 #if TEST_STD_VER >= 11
113 X x[3] = {X(1), X(2), X(3)};
114 Y y[3] = {Y(1), Y(2), Y(3)};
115 std::adjacent_difference(x, x+3, y);
116 #endif
117
118 return true;
119 }
120
main(int,char **)121 int main(int, char**)
122 {
123 test();
124 #if TEST_STD_VER > 17
125 static_assert(test());
126 #endif
127 return 0;
128 }
129