What is a future in Rust?
In Rust, a future represents a value that may not be available immediately but will be available at some point in the future. It is an abstraction that allows you to work with asynchronous programming and handle tasks that may take time to complete, such as I/O operations, network requests, or computations.
Futures in Rust are based on the asynchronous programming model called "futures and tasks." The core concept is the `Future` trait, defined in the `std::future` module. The `Future` trait represents an asynchronous computation that yields a value or an error. Futures are composable, meaning you can combine multiple futures together to form more complex asynchronous workflows.
