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// UNSUPPORTED: c++03, c++11, c++14
10
11// UNSUPPORTED: libcpp-has-no-incomplete-pstl
12
13// <algorithm>
14
15// template<class ExecutionPolicy, class ForwardIterator, class Size, class Function>
16// ForwardIterator for_each_n(ExecutionPolicy&& exec, ForwardIterator first, Size n,
17// Function f);
18
19#include <algorithm>
20#include <atomic>
21#include <cassert>
22#include <vector>
23
24#include "test_macros.h"
25#include "test_execution_policies.h"
26#include "test_iterators.h"
27
28EXECUTION_POLICY_SFINAE_TEST(for_each_n);
29
30static_assert(sfinae_test_for_each_n<int, int*, int, bool (*)(int)>);
31static_assert(!sfinae_test_for_each_n<std::execution::parallel_policy, int*, int, bool (*)(int)>);
32
33template <class Iter>
34struct Test {
35 template <class Policy>
36 void operator()(Policy&& policy) {
37 int sizes[] = {0, 1, 2, 100};
38 for (auto size : sizes) {
39 std::vector<int> a(size);
40 std::vector<Bool> called(size);
41 std::for_each_n(policy, Iter(std::data(cont&: a)), std::size(cont: a), [&](int& v) {
42 assert(!called[&v - a.data()]);
43 called[&v - a.data()] = true;
44 });
45 assert(std::all_of(std::begin(called), std::end(called), [](bool b) { return b; }));
46 }
47 }
48};
49
50int main(int, char**) {
51 types::for_each(types::forward_iterator_list<int*>{}, TestIteratorWithPolicies<Test>{});
52
53 return 0;
54}
55

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