Monitoring things using futures

Futures are a great tool in the tool chest of every programmer. But, wait! What's a future?

Well, while a task can be seen as a sort of asynchronous procedure, a future can be seen as an asynchronous function. However, while using task, the process is quite clear (it runs in the background and uses some sort of messaging to talk to the other thread) the future is a bit more complex. When should I get the return value of the future? Let's talk about futures with an example. You can use futures to run tasks on a separate thread and then forget about them, but often, you'll want to use the result of the task. The future function returns an IFuture<T> reference that you can use to request the result of type T. The reference is like the ticket that a dry cleaner gives you: at any time you can use it to request your clean dress, but if your dress isn't clean yet, you'll have to wait. Similarly, you can use the reference value to request a future's result, but...