A non-blocking iterator over messages in a channel.

Each call to next returns a message if there is one ready to be received. The iterator never blocks waiting for the next message.

Examples

use std::thread;
use std::time::Duration;
use crossbeam_channel::unbounded;

let (s, r) = unbounded::<i32>();

thread::spawn(move || {
    s.send(1).unwrap();
    thread::sleep(Duration::from_secs(1));
    s.send(2).unwrap();
    thread::sleep(Duration::from_secs(2));
    s.send(3).unwrap();
});

thread::sleep(Duration::from_secs(2));

// Collect all messages from the channel without blocking.
// The third message hasn't been sent yet so we'll collect only the first two.
let v: Vec<_> = r.try_iter().collect();

assert_eq!(v, [1, 2]);