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 // future<R> get_future();
15 
16 #include <future>
17 #include <cassert>
18 
19 class A
20 {
21     long data_;
22 
23 public:
A(long i)24     explicit A(long i) : data_(i) {}
25 
operator ()(long i,long j) const26     long operator()(long i, long j) const {return data_ + i + j;}
27 };
28 
main()29 int main()
30 {
31     {
32         std::packaged_task<double(int, char)> p(A(5));
33         std::future<double> f = p.get_future();
34         p(3, 'a');
35         assert(f.get() == 105.0);
36     }
37     {
38         std::packaged_task<double(int, char)> p(A(5));
39         std::future<double> f = p.get_future();
40         try
41         {
42             f = p.get_future();
43             assert(false);
44         }
45         catch (const std::future_error& e)
46         {
47             assert(e.code() ==  make_error_code(std::future_errc::future_already_retrieved));
48         }
49     }
50     {
51         std::packaged_task<double(int, char)> p;
52         try
53         {
54             std::future<double> f = p.get_future();
55             assert(false);
56         }
57         catch (const std::future_error& e)
58         {
59             assert(e.code() ==  make_error_code(std::future_errc::no_state));
60         }
61     }
62 }
63