Trait futures::task::SpawnExt

source · [−]
pub trait SpawnExt: Spawn {
    fn spawn<Fut>(&self, future: Fut) -> Result<(), SpawnError>
    where
        Fut: 'static + Future<Output = ()> + Send,
    { ... }

    fn spawn_with_handle<Fut>(
        &self, 
        future: Fut
    ) -> Result<RemoteHandle<<Fut as Future>::Output>, SpawnError>
    where
        Fut: 'static + Future + Send,
        <Fut as Future>::Output: Send,
    { ... }
}
Expand description

Extension trait for Spawn.

Provided methods

Spawns a task that polls the given future with output () to completion.

This method returns a Result that contains a SpawnError if spawning fails.

You can use spawn_with_handle if you want to spawn a future with output other than () or if you want to be able to await its completion.

Note this method will eventually be replaced with the upcoming Spawn::spawn method which will take a dyn Future as input. Technical limitations prevent Spawn::spawn from being implemented today. Feel free to use this method in the meantime.

use futures::executor::ThreadPool;
use futures::task::SpawnExt;

let executor = ThreadPool::new().unwrap();

let future = async { /* ... */ };
executor.spawn(future).unwrap();

Spawns a task that polls the given future to completion and returns a future that resolves to the spawned future’s output.

This method returns a Result that contains a RemoteHandle, or, if spawning fails, a SpawnError. RemoteHandle is a future that resolves to the output of the spawned future.

use futures::executor::{block_on, ThreadPool};
use futures::future;
use futures::task::SpawnExt;

let executor = ThreadPool::new().unwrap();

let future = future::ready(1);
let join_handle_fut = executor.spawn_with_handle(future).unwrap();
assert_eq!(block_on(join_handle_fut), 1);

Implementors