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 // <algorithm>
10 
11 // template<InputIterator InIter1, InputIterator InIter2, class OutIter,
12 //          Callable<auto, const InIter1::value_type&, const InIter2::value_type&> BinaryOp>
13 //   requires OutputIterator<OutIter, BinaryOp::result_type> && CopyConstructible<BinaryOp>
14 // constexpr OutIter      // constexpr after C++17
15 // transform(InIter1 first1, InIter1 last1, InIter2 first2, OutIter result, BinaryOp binary_op);
16 
17 #include <algorithm>
18 #include <functional>
19 #include <cassert>
20 
21 #include "test_macros.h"
22 #include "test_iterators.h"
23 
24 #if TEST_STD_VER > 17
test_constexpr()25 TEST_CONSTEXPR bool test_constexpr() {
26     const int ia[] = {1, 3, 6, 7};
27     const int ib[] = {2, 4, 7, 8};
28           int ic[] = {0, 0, 0, 0, 0}; // one bigger
29     const int expected[] = {3, 7, 13, 15};
30 
31     auto it = std::transform(std::begin(ia), std::end(ia),
32                              std::begin(ib), std::begin(ic), std::plus<int>());
33 
34     return it == (std::begin(ic) + std::size(ia))
35         && *it == 0 // don't overwrite the last value in the output array
36         && std::equal(std::begin(expected), std::end(expected), std::begin(ic), it)
37         ;
38     }
39 #endif
40 
41 
42 template<class InIter1, class InIter2, class OutIter>
43 void
test()44 test()
45 {
46     int ia[] = {0, 1, 2, 3, 4};
47     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
48     int ib[sa] = {1, 2, 3, 4, 5};
49     OutIter r = std::transform(InIter1(ib), InIter1(ib+sa), InIter2(ia),
50                                OutIter(ib), std::minus<int>());
51     assert(base(r) == ib + sa);
52     assert(ib[0] == 1);
53     assert(ib[1] == 1);
54     assert(ib[2] == 1);
55     assert(ib[3] == 1);
56     assert(ib[4] == 1);
57 }
58 
main(int,char **)59 int main(int, char**)
60 {
61     test<cpp17_input_iterator<const int*>, cpp17_input_iterator<const int*>, cpp17_output_iterator<int*> >();
62     test<cpp17_input_iterator<const int*>, cpp17_input_iterator<const int*>, cpp17_input_iterator<int*> >();
63     test<cpp17_input_iterator<const int*>, cpp17_input_iterator<const int*>, forward_iterator<int*> >();
64     test<cpp17_input_iterator<const int*>, cpp17_input_iterator<const int*>, bidirectional_iterator<int*> >();
65     test<cpp17_input_iterator<const int*>, cpp17_input_iterator<const int*>, random_access_iterator<int*> >();
66     test<cpp17_input_iterator<const int*>, cpp17_input_iterator<const int*>, int*>();
67 
68     test<cpp17_input_iterator<const int*>, forward_iterator<const int*>, cpp17_output_iterator<int*> >();
69     test<cpp17_input_iterator<const int*>, forward_iterator<const int*>, cpp17_input_iterator<int*> >();
70     test<cpp17_input_iterator<const int*>, forward_iterator<const int*>, forward_iterator<int*> >();
71     test<cpp17_input_iterator<const int*>, forward_iterator<const int*>, bidirectional_iterator<int*> >();
72     test<cpp17_input_iterator<const int*>, forward_iterator<const int*>, random_access_iterator<int*> >();
73     test<cpp17_input_iterator<const int*>, forward_iterator<const int*>, int*>();
74 
75     test<cpp17_input_iterator<const int*>, bidirectional_iterator<const int*>, cpp17_output_iterator<int*> >();
76     test<cpp17_input_iterator<const int*>, bidirectional_iterator<const int*>, cpp17_input_iterator<int*> >();
77     test<cpp17_input_iterator<const int*>, bidirectional_iterator<const int*>, forward_iterator<int*> >();
78     test<cpp17_input_iterator<const int*>, bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
79     test<cpp17_input_iterator<const int*>, bidirectional_iterator<const int*>, random_access_iterator<int*> >();
80     test<cpp17_input_iterator<const int*>, bidirectional_iterator<const int*>, int*>();
81 
82     test<cpp17_input_iterator<const int*>, random_access_iterator<const int*>, cpp17_output_iterator<int*> >();
83     test<cpp17_input_iterator<const int*>, random_access_iterator<const int*>, cpp17_input_iterator<int*> >();
84     test<cpp17_input_iterator<const int*>, random_access_iterator<const int*>, forward_iterator<int*> >();
85     test<cpp17_input_iterator<const int*>, random_access_iterator<const int*>, bidirectional_iterator<int*> >();
86     test<cpp17_input_iterator<const int*>, random_access_iterator<const int*>, random_access_iterator<int*> >();
87     test<cpp17_input_iterator<const int*>, random_access_iterator<const int*>, int*>();
88 
89     test<cpp17_input_iterator<const int*>, const int*, cpp17_output_iterator<int*> >();
90     test<cpp17_input_iterator<const int*>, const int*, cpp17_input_iterator<int*> >();
91     test<cpp17_input_iterator<const int*>, const int*, forward_iterator<int*> >();
92     test<cpp17_input_iterator<const int*>, const int*, bidirectional_iterator<int*> >();
93     test<cpp17_input_iterator<const int*>, const int*, random_access_iterator<int*> >();
94     test<cpp17_input_iterator<const int*>, const int*, int*>();
95 
96     test<forward_iterator<const int*>, cpp17_input_iterator<const int*>, cpp17_output_iterator<int*> >();
97     test<forward_iterator<const int*>, cpp17_input_iterator<const int*>, cpp17_input_iterator<int*> >();
98     test<forward_iterator<const int*>, cpp17_input_iterator<const int*>, forward_iterator<int*> >();
99     test<forward_iterator<const int*>, cpp17_input_iterator<const int*>, bidirectional_iterator<int*> >();
100     test<forward_iterator<const int*>, cpp17_input_iterator<const int*>, random_access_iterator<int*> >();
101     test<forward_iterator<const int*>, cpp17_input_iterator<const int*>, int*>();
102 
103     test<forward_iterator<const int*>, forward_iterator<const int*>, cpp17_output_iterator<int*> >();
104     test<forward_iterator<const int*>, forward_iterator<const int*>, cpp17_input_iterator<int*> >();
105     test<forward_iterator<const int*>, forward_iterator<const int*>, forward_iterator<int*> >();
106     test<forward_iterator<const int*>, forward_iterator<const int*>, bidirectional_iterator<int*> >();
107     test<forward_iterator<const int*>, forward_iterator<const int*>, random_access_iterator<int*> >();
108     test<forward_iterator<const int*>, forward_iterator<const int*>, int*>();
109 
110     test<forward_iterator<const int*>, bidirectional_iterator<const int*>, cpp17_output_iterator<int*> >();
111     test<forward_iterator<const int*>, bidirectional_iterator<const int*>, cpp17_input_iterator<int*> >();
112     test<forward_iterator<const int*>, bidirectional_iterator<const int*>, forward_iterator<int*> >();
113     test<forward_iterator<const int*>, bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
114     test<forward_iterator<const int*>, bidirectional_iterator<const int*>, random_access_iterator<int*> >();
115     test<forward_iterator<const int*>, bidirectional_iterator<const int*>, int*>();
116 
117     test<forward_iterator<const int*>, random_access_iterator<const int*>, cpp17_output_iterator<int*> >();
118     test<forward_iterator<const int*>, random_access_iterator<const int*>, cpp17_input_iterator<int*> >();
119     test<forward_iterator<const int*>, random_access_iterator<const int*>, forward_iterator<int*> >();
120     test<forward_iterator<const int*>, random_access_iterator<const int*>, bidirectional_iterator<int*> >();
121     test<forward_iterator<const int*>, random_access_iterator<const int*>, random_access_iterator<int*> >();
122     test<forward_iterator<const int*>, random_access_iterator<const int*>, int*>();
123 
124     test<forward_iterator<const int*>, const int*, cpp17_output_iterator<int*> >();
125     test<forward_iterator<const int*>, const int*, cpp17_input_iterator<int*> >();
126     test<forward_iterator<const int*>, const int*, forward_iterator<int*> >();
127     test<forward_iterator<const int*>, const int*, bidirectional_iterator<int*> >();
128     test<forward_iterator<const int*>, const int*, random_access_iterator<int*> >();
129     test<forward_iterator<const int*>, const int*, int*>();
130 
131     test<bidirectional_iterator<const int*>, cpp17_input_iterator<const int*>, cpp17_output_iterator<int*> >();
132     test<bidirectional_iterator<const int*>, cpp17_input_iterator<const int*>, cpp17_input_iterator<int*> >();
133     test<bidirectional_iterator<const int*>, cpp17_input_iterator<const int*>, forward_iterator<int*> >();
134     test<bidirectional_iterator<const int*>, cpp17_input_iterator<const int*>, bidirectional_iterator<int*> >();
135     test<bidirectional_iterator<const int*>, cpp17_input_iterator<const int*>, random_access_iterator<int*> >();
136     test<bidirectional_iterator<const int*>, cpp17_input_iterator<const int*>, int*>();
137 
138     test<bidirectional_iterator<const int*>, forward_iterator<const int*>, cpp17_output_iterator<int*> >();
139     test<bidirectional_iterator<const int*>, forward_iterator<const int*>, cpp17_input_iterator<int*> >();
140     test<bidirectional_iterator<const int*>, forward_iterator<const int*>, forward_iterator<int*> >();
141     test<bidirectional_iterator<const int*>, forward_iterator<const int*>, bidirectional_iterator<int*> >();
142     test<bidirectional_iterator<const int*>, forward_iterator<const int*>, random_access_iterator<int*> >();
143     test<bidirectional_iterator<const int*>, forward_iterator<const int*>, int*>();
144 
145     test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*>, cpp17_output_iterator<int*> >();
146     test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*>, cpp17_input_iterator<int*> >();
147     test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*>, forward_iterator<int*> >();
148     test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
149     test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*>, random_access_iterator<int*> >();
150     test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*>, int*>();
151 
152     test<bidirectional_iterator<const int*>, random_access_iterator<const int*>, cpp17_output_iterator<int*> >();
153     test<bidirectional_iterator<const int*>, random_access_iterator<const int*>, cpp17_input_iterator<int*> >();
154     test<bidirectional_iterator<const int*>, random_access_iterator<const int*>, forward_iterator<int*> >();
155     test<bidirectional_iterator<const int*>, random_access_iterator<const int*>, bidirectional_iterator<int*> >();
156     test<bidirectional_iterator<const int*>, random_access_iterator<const int*>, random_access_iterator<int*> >();
157     test<bidirectional_iterator<const int*>, random_access_iterator<const int*>, int*>();
158 
159     test<bidirectional_iterator<const int*>, const int*, cpp17_output_iterator<int*> >();
160     test<bidirectional_iterator<const int*>, const int*, cpp17_input_iterator<int*> >();
161     test<bidirectional_iterator<const int*>, const int*, forward_iterator<int*> >();
162     test<bidirectional_iterator<const int*>, const int*, bidirectional_iterator<int*> >();
163     test<bidirectional_iterator<const int*>, const int*, random_access_iterator<int*> >();
164     test<bidirectional_iterator<const int*>, const int*, int*>();
165 
166     test<random_access_iterator<const int*>, cpp17_input_iterator<const int*>, cpp17_output_iterator<int*> >();
167     test<random_access_iterator<const int*>, cpp17_input_iterator<const int*>, cpp17_input_iterator<int*> >();
168     test<random_access_iterator<const int*>, cpp17_input_iterator<const int*>, forward_iterator<int*> >();
169     test<random_access_iterator<const int*>, cpp17_input_iterator<const int*>, bidirectional_iterator<int*> >();
170     test<random_access_iterator<const int*>, cpp17_input_iterator<const int*>, random_access_iterator<int*> >();
171     test<random_access_iterator<const int*>, cpp17_input_iterator<const int*>, int*>();
172 
173     test<random_access_iterator<const int*>, forward_iterator<const int*>, cpp17_output_iterator<int*> >();
174     test<random_access_iterator<const int*>, forward_iterator<const int*>, cpp17_input_iterator<int*> >();
175     test<random_access_iterator<const int*>, forward_iterator<const int*>, forward_iterator<int*> >();
176     test<random_access_iterator<const int*>, forward_iterator<const int*>, bidirectional_iterator<int*> >();
177     test<random_access_iterator<const int*>, forward_iterator<const int*>, random_access_iterator<int*> >();
178     test<random_access_iterator<const int*>, forward_iterator<const int*>, int*>();
179 
180     test<random_access_iterator<const int*>, bidirectional_iterator<const int*>, cpp17_output_iterator<int*> >();
181     test<random_access_iterator<const int*>, bidirectional_iterator<const int*>, cpp17_input_iterator<int*> >();
182     test<random_access_iterator<const int*>, bidirectional_iterator<const int*>, forward_iterator<int*> >();
183     test<random_access_iterator<const int*>, bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
184     test<random_access_iterator<const int*>, bidirectional_iterator<const int*>, random_access_iterator<int*> >();
185     test<random_access_iterator<const int*>, bidirectional_iterator<const int*>, int*>();
186 
187     test<random_access_iterator<const int*>, random_access_iterator<const int*>, cpp17_output_iterator<int*> >();
188     test<random_access_iterator<const int*>, random_access_iterator<const int*>, cpp17_input_iterator<int*> >();
189     test<random_access_iterator<const int*>, random_access_iterator<const int*>, forward_iterator<int*> >();
190     test<random_access_iterator<const int*>, random_access_iterator<const int*>, bidirectional_iterator<int*> >();
191     test<random_access_iterator<const int*>, random_access_iterator<const int*>, random_access_iterator<int*> >();
192     test<random_access_iterator<const int*>, random_access_iterator<const int*>, int*>();
193 
194     test<random_access_iterator<const int*>, const int*, cpp17_output_iterator<int*> >();
195     test<random_access_iterator<const int*>, const int*, cpp17_input_iterator<int*> >();
196     test<random_access_iterator<const int*>, const int*, forward_iterator<int*> >();
197     test<random_access_iterator<const int*>, const int*, bidirectional_iterator<int*> >();
198     test<random_access_iterator<const int*>, const int*, random_access_iterator<int*> >();
199     test<random_access_iterator<const int*>, const int*, int*>();
200 
201     test<const int*, cpp17_input_iterator<const int*>, cpp17_output_iterator<int*> >();
202     test<const int*, cpp17_input_iterator<const int*>, cpp17_input_iterator<int*> >();
203     test<const int*, cpp17_input_iterator<const int*>, forward_iterator<int*> >();
204     test<const int*, cpp17_input_iterator<const int*>, bidirectional_iterator<int*> >();
205     test<const int*, cpp17_input_iterator<const int*>, random_access_iterator<int*> >();
206     test<const int*, cpp17_input_iterator<const int*>, int*>();
207 
208     test<const int*, forward_iterator<const int*>, cpp17_output_iterator<int*> >();
209     test<const int*, forward_iterator<const int*>, cpp17_input_iterator<int*> >();
210     test<const int*, forward_iterator<const int*>, forward_iterator<int*> >();
211     test<const int*, forward_iterator<const int*>, bidirectional_iterator<int*> >();
212     test<const int*, forward_iterator<const int*>, random_access_iterator<int*> >();
213     test<const int*, forward_iterator<const int*>, int*>();
214 
215     test<const int*, bidirectional_iterator<const int*>, cpp17_output_iterator<int*> >();
216     test<const int*, bidirectional_iterator<const int*>, cpp17_input_iterator<int*> >();
217     test<const int*, bidirectional_iterator<const int*>, forward_iterator<int*> >();
218     test<const int*, bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
219     test<const int*, bidirectional_iterator<const int*>, random_access_iterator<int*> >();
220     test<const int*, bidirectional_iterator<const int*>, int*>();
221 
222     test<const int*, random_access_iterator<const int*>, cpp17_output_iterator<int*> >();
223     test<const int*, random_access_iterator<const int*>, cpp17_input_iterator<int*> >();
224     test<const int*, random_access_iterator<const int*>, forward_iterator<int*> >();
225     test<const int*, random_access_iterator<const int*>, bidirectional_iterator<int*> >();
226     test<const int*, random_access_iterator<const int*>, random_access_iterator<int*> >();
227     test<const int*, random_access_iterator<const int*>, int*>();
228 
229     test<const int*, const int*, cpp17_output_iterator<int*> >();
230     test<const int*, const int*, cpp17_input_iterator<int*> >();
231     test<const int*, const int*, forward_iterator<int*> >();
232     test<const int*, const int*, bidirectional_iterator<int*> >();
233     test<const int*, const int*, random_access_iterator<int*> >();
234     test<const int*, const int*, int*>();
235 
236 #if TEST_STD_VER > 17
237     static_assert(test_constexpr());
238 #endif
239 
240   return 0;
241 }
242