A blocking iterator over messages in a channel.

Each call to next blocks waiting for the next message and then returns it. However, if the channel becomes empty and disconnected, it returns None without blocking.

Examples

use std::thread;
use crossbeam_channel::unbounded;

let (s, r) = unbounded();

thread::spawn(move || {
    s.send(1).unwrap();
    s.send(2).unwrap();
    s.send(3).unwrap();
    drop(s); // Disconnect the channel.
});

// Collect all messages from the channel.
// Note that the call to `collect` blocks until the sender is dropped.
let v: Vec<_> = r.into_iter().collect();

assert_eq!(v, [1, 2, 3]);