What are idiomatic ways to send data between threads?

Question

I want to do some calculation in a separate thread, and then recover the data from the main thread. What are the canonical ways to pass some data from a thread to another in

Answer 1

The idiomatic way to do so is to use a channel. It conceptually behaves like an unidirectional tunnel: you put something in one end and it comes out the other side.

use std::sync::mpsc::channel;

fn main() {
    let (sender, receiver) = channel();

    let handle = std::thread::spawn(move || {
        sender.send(String::from("Hello world!")).unwrap();
    });

    let data = receiver.recv().unwrap();
    println!("Got {:?}", data);

    handle.join().unwrap();
}

The channel won't work anymore when the receiver is dropped.

They are mainly 3 ways to recover the data:

• recv will block until something is received
• try_recv will return immediately. If the channel is not closed, it is either Ok(data) or Err(TryRevcError::Empty).
• recv_timeout is the same as try_recv but it waits to get a data a certain amount of time.