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// constexpr Function // constexpr since C++20
13// for_each(Iter first, Iter last, Function f);
14
15#include <algorithm>
16#include <cassert>
17#include <deque>
18#if __has_include(<ranges>)
19# include <ranges>
20#endif
21#include <vector>
22
23#include "test_macros.h"
24#include "test_iterators.h"
25
26struct for_each_test {
27 TEST_CONSTEXPR for_each_test(int c) : count(c) {}
28
29 // for_each functors only have to be move constructible
30 for_each_test(const for_each_test&) = delete;
31 for_each_test(for_each_test&&) = default;
32 for_each_test& operator=(const for_each_test&) = delete;
33 for_each_test& operator=(for_each_test&&) = delete;
34
35 int count;
36 TEST_CONSTEXPR_CXX14 void operator()(int& i) {
37 ++i;
38 ++count;
39 }
40};
41
42struct Test {
43 template <class Iter>
44 TEST_CONSTEXPR_CXX20 void operator()() {
45 int sizes[] = {0, 1, 6};
46 for (const int size : sizes) {
47 int ia[] = {0, 1, 2, 3, 4, 5};
48 for_each_test f = std::for_each(Iter(ia), Iter(ia + size), for_each_test(0));
49 assert(f.count == size);
50 for (int i = 0; i < size; ++i)
51 assert(ia[i] == static_cast<int>(i + 1));
52 }
53 }
54};
55
56TEST_CONSTEXPR_CXX20 bool test() {
57 types::for_each(types::cpp17_input_iterator_list<int*>(), Test());
58
59 // TODO: Remove the `_LIBCPP_ENABLE_EXPERIMENTAL` check once we have the FTM guarded or views::join isn't
60 // experimental anymore
61#if TEST_STD_VER >= 20 && defined(_LIBCPP_ENABLE_EXPERIMENTAL)
62 { // Make sure that the segmented iterator optimization works during constant evaluation
63 std::vector<std::vector<int>> vecs = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
64 auto v = std::views::join(vecs);
65 std::for_each(v.begin(), v.end(), [i = 0](int& a) mutable { assert(a == ++i); });
66 }
67#endif
68
69 return true;
70}
71
72struct deque_test {
73 std::deque<int>* d_;
74 int* i_;
75
76 deque_test(std::deque<int>& d, int& i) : d_(&d), i_(&i) {}
77
78 void operator()(int& v) {
79 assert(&(*d_)[*i_] == &v);
80 ++*i_;
81 }
82};
83
84int main(int, char**) {
85 test();
86#if TEST_STD_VER >= 20
87 static_assert(test());
88#endif
89
90 // check that segmented iterators work properly
91 int sizes[] = {0, 1, 2, 1023, 1024, 1025, 2047, 2048, 2049};
92 for (const int size : sizes) {
93 std::deque<int> d(size);
94 int index = 0;
95
96 std::for_each(first: d.begin(), last: d.end(), f: deque_test(d, index));
97 }
98
99 return 0;
100}
101

source code of libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each.pass.cpp