Trait event_listener_strategy::Strategy

source ·

pub trait Strategy<'a> {
    type Context: ?Sized;
    type Future: Future + 'a;

    // Required methods
    fn poll<T>(
        &mut self,
        event_listener: Pin<&mut EventListener<T>>,
        context: &mut Self::Context
    ) -> Poll<T>;
    fn wait(&mut self, evl: Pin<&'a mut EventListener>) -> Self::Future;
}

Expand description

A strategy for polling an EventListenerFuture or an EventListener.

This trait is used by the EventListenerFuture::poll_with_strategy method to determine how to poll the future. It can also be used standalone, by calling the Strategy::wait method.

Examples

use event_listener::{Event, EventListener};
use event_listener_strategy::{EventListenerFuture, Strategy, Blocking, NonBlocking};
use std::pin::Pin;

async fn wait_on<'a, S: Strategy<'a>>(evl: Pin<&'a mut EventListener>, strategy: &mut S) {
    strategy.wait(evl).await;
}

// Block on the future.
let ev = Event::new();
let mut listener = ev.listen();
ev.notify(1);

wait_on(listener.as_mut(), &mut Blocking::default()).await;

// Poll the future.
listener.as_mut().listen(&ev);
ev.notify(1);

wait_on(listener.as_mut(), &mut NonBlocking::default()).await;