xref: /minix3/external/bsd/libc++/dist/libcxx/test/thread/futures/futures.tas/futures.task.nonmembers/swap.pass.cpp (revision 4684ddb6aab0b36791c8099bc705d6140b3d05d0)
1 //===----------------------------------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // <future>
11 
12 // class packaged_task<R(ArgTypes...)>
13 
14 // template <class R, class... ArgTypes>
15 //   void
16 //   swap(packaged_task<R(ArgTypes...)>& x, packaged_task<R(ArgTypes...)>& y);
17 
18 #include <future>
19 #include <cassert>
20 
21 class A
22 {
23     long data_;
24 
25 public:
A(long i)26     explicit A(long i) : data_(i) {}
27 
operator ()(long i,long j) const28     long operator()(long i, long j) const {return data_ + i + j;}
29 };
30 
main()31 int main()
32 {
33     {
34         std::packaged_task<double(int, char)> p0(A(5));
35         std::packaged_task<double(int, char)> p;
36         swap(p, p0);
37         assert(!p0.valid());
38         assert(p.valid());
39         std::future<double> f = p.get_future();
40         p(3, 'a');
41         assert(f.get() == 105.0);
42     }
43     {
44         std::packaged_task<double(int, char)> p0;
45         std::packaged_task<double(int, char)> p;
46         swap(p, p0);
47         assert(!p0.valid());
48         assert(!p.valid());
49     }
50 }
51