【】future用法

 1 #include <iostream>
 2 #include <thread>
 3 #include <future>
 4 
 5 using namespace std;
 6 
 7 void DoWork(promise<int> thePromise)
 8 {
 9     // ... Do some work ...
10     // And ultimately store the result in the promise.
11     thePromise.set_value(42);
12 }
13 
14 int main()
15 {
16     // Create a promise to pass to the thread.
17     promise<int> myPromise;
18     // Get the future of the promise.
19     std::future<int> theFuture = myPromise.get_future();
20     // Create a thread and move the promise into it.
21     thread theThread{ DoWork, std::move(myPromise) };
22 
23     // Do some more work...
24 
25     // Get the result.
26     int result = theFuture.get();
27     cout << "Result: " << result << endl;
28 
29     // Make sure to join the thread.
30     theThread.join();
31 
32     return 0;
33 }