pub fn channel<T>(init: T) -> (Sender<T>, Receiver<T>)
Expand description
Creates a new watch channel, returning the “send” and “receive” handles.
All values sent by Sender
will become visible to the Receiver
handles.
Only the last value sent is made available to the Receiver
half. All
intermediate values are dropped.
§Examples
The following example prints hello! world!
.
use tokio::sync::watch;
use tokio::time::{Duration, sleep};
let (tx, mut rx) = watch::channel("hello");
tokio::spawn(async move {
// Use the equivalent of a "do-while" loop so the initial value is
// processed before awaiting the `changed()` future.
loop {
println!("{}! ", *rx.borrow_and_update());
if rx.changed().await.is_err() {
break;
}
}
});
sleep(Duration::from_millis(100)).await;
tx.send("world")?;