Function crossbeam_channel::bounded

pub fn bounded<T>(cap: usize) -> (Sender<T>, Receiver<T>)

Creates a channel of bounded capacity.

This channel has a buffer that can hold at most cap messages at a time.

A special case is zero-capacity channel, which cannot hold any messages. Instead, send and receive operations must appear at the same time in order to pair up and pass the message over.

Panics

Panics if the capacity is greater than usize::max_value() / 4.

Examples

A channel of capacity 1:

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

let (s, r) = bounded(1);

// This call returns immediately because there is enough space in the channel.
s.send(1).unwrap();

thread::spawn(move || {
    // This call blocks the current thread because the channel is full.
    // It will be able to complete only after the first message is received.
    s.send(2).unwrap();
});

thread::sleep(Duration::from_secs(1));
assert_eq!(r.recv(), Ok(1));
assert_eq!(r.recv(), Ok(2));

A zero-capacity channel:

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

let (s, r) = bounded(0);

thread::spawn(move || {
    // This call blocks the current thread until a receive operation appears
    // on the other side of the channel.
    s.send(1).unwrap();
});

thread::sleep(Duration::from_secs(1));
assert_eq!(r.recv(), Ok(1));