如何在不使用Future标头的情况下从线程返回值？

Question

My current compiler doesn't support the future header, and I'm unable to update it as on Android, the compiler is wrapped in an app. Because of this, I decided to try to make my own simple future class. I have most of it laid out, but can't figure out how to get the return value from the thread (as this seems to be beyond its intended use). I could pass my future class a functor that contains it's own return holder variable to be retrieved later, but that's a little limiting, because anything I wanted to pass it would have to be derived from the original functors class, and not just a function.

Is there any way to achieve this? I'm assuming the standard future header doesn't use black magic to do it. Does it use a "different version" of threads that allow it to receive a value back?

(It's not so old as to not be compatible with threading, it just has issues with the future header for some reason)

Thanks

Answer 1

I think by writing your own simple Future class you're on the right way. What does your code look like?

I'm not sure if I fully understand your statement:

I could pass my future class a functor that contains it's own return holder variable to be retrieved later, but that's a little limiting, because anything I wanted to pass it would have to be derived from the original functors class, and not just a function.

I wouldn't pass a functor but only store variables for the values I want as return values from the thread. If you want different return values you could derive classes from your SimpleFuture class.