What are C++ futures and how do they work?

What are C++ futures and how do they work?

C++ futures are a way to retrieve values from asynchronous operations. They allow you to run tasks in the background and get the result later.

Can you give me an example of how to use futures in C++?

Sure! You can use std::async to run a function asynchronously and get a future object. Here's a simple example:

#include <iostream>
#include <future>

int compute() {
    return 42;
}

int main() {
    std::future<int> result = std::async(compute);
    std::cout << "Result: " << result.get() << std::endl;
    return 0;
}

What happens if I try to get the result of a future that hasn't completed?

If you call get() on a future that hasn't completed, it will block the calling thread until the result is available. If the asynchronous operation fails, it will throw an exception.

Are there any limitations or considerations when using futures?

Yes, you should be aware of potential exceptions, the need for proper synchronization, and the overhead of managing asynchronous tasks.