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 Iter, Callable<auto, Iter::reference> Function>
12 //   requires CopyConstructible<Function>
13 //   constexpr Function   // constexpr after C++17
14 //   for_each(Iter first, Iter last, Function f);
15 
16 #include <algorithm>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 #include "test_iterators.h"
21 
22 #if TEST_STD_VER > 17
test_constexpr()23 TEST_CONSTEXPR bool test_constexpr() {
24     int ia[] = {1, 3, 6, 7};
25     int expected[] = {3, 5, 8, 9};
26 
27     std::for_each(std::begin(ia), std::end(ia), [](int &a) { a += 2; });
28     return std::equal(std::begin(ia), std::end(ia), std::begin(expected))
29         ;
30     }
31 #endif
32 
33 struct for_each_test
34 {
for_each_testfor_each_test35     for_each_test(int c) : count(c) {}
36     int count;
operator ()for_each_test37     void operator()(int& i) {++i; ++count;}
38 };
39 
main(int,char **)40 int main(int, char**)
41 {
42     int ia[] = {0, 1, 2, 3, 4, 5};
43     const unsigned s = sizeof(ia)/sizeof(ia[0]);
44     for_each_test f = std::for_each(input_iterator<int*>(ia),
45                                     input_iterator<int*>(ia+s),
46                                     for_each_test(0));
47     assert(f.count == s);
48     for (unsigned i = 0; i < s; ++i)
49         assert(ia[i] == static_cast<int>(i+1));
50 
51 #if TEST_STD_VER > 17
52     static_assert(test_constexpr());
53 #endif
54 
55   return 0;
56 }
57