Rust Essentials - Second Edition

Making a channel

An elegant code pattern is shown in the following code snippet, where the channel is created in the make_chan() function, which returns the receiving endpoint for the calling code:

// code from Chapter 9/code/make_channel.rs: 
use std::sync::mpsc::channel; 
use std::sync::mpsc::Receiver; 
fn make_chan() -> Receiver<i32> {    let (tx, rx) = channel();    tx.send(7).unwrap();    rx} 
fn main() { 
    let rx = make_chan(); 
    if let Some(msg) = rx.recv().ok() { 
      println!("received message {}", msg); 
    }; 
} 

This prints out the following:

received message 7