Struct tokio_sync::mpsc::Receiver

pub struct Receiver<T> { /* fields omitted */ }

Receive values from the associated Sender.

Instances are created by the channel function.

Methods

impl<T> Receiver<T>

pub async fn recv<'_>(&'_ mut self) -> Option<T>

Receive the next value for this receiver.

None is returned when all Sender halves have dropped, indicating that no further values can be sent on the channel.

Examples

use tokio::sync::mpsc;

#[tokio::main]
async fn main() {
    let (mut tx, mut rx) = mpsc::channel(100);

    tokio::spawn(async move {
        tx.send("hello").await.unwrap();
    });

    assert_eq!(Some("hello"), rx.recv().await);
    assert_eq!(None, rx.recv().await);
}

Values are buffered:

use tokio::sync::mpsc;

#[tokio::main]
async fn main() {
    let (mut tx, mut rx) = mpsc::channel(100);

    tx.send("hello").await.unwrap();
    tx.send("world").await.unwrap();

    assert_eq!(Some("hello"), rx.recv().await);
    assert_eq!(Some("world"), rx.recv().await);
}

pub fn close(&mut self)

Closes the receiving half of a channel, without dropping it.

This prevents any further messages from being sent on the channel while still enabling the receiver to drain messages that are buffered.

Trait Implementations

impl<T> Debug for Receiver<T>

fn fmt(&self, fmt: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<T> Stream for Receiver<T>

type Item = T

Values yielded by the stream.

fn poll_next(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<T>>

Attempt to pull out the next value of this stream, registering the current task for wakeup if the value is not yet available, and returning None if the stream is exhausted.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the stream.