Struct ScopeFuture

pub struct ScopeFuture<Fut, Joiner>
where
    Fut: Future,
{ /* private fields */ }

A future that manages a scope.

This future is created by scope function.

Implementations

impl<Fut, Joiner> ScopeFuture<Fut, Joiner>

where Fut: Future,

pub fn cancel(self: Pin<&mut Self>)

Initiates a graceful cancellation.

This function will send a wakeup signal to all the cancellation futures in the scope. Tasks in the scope can continue execution, but they are expected to stop the subsequent processing during the grace period.

The cancellation signal will be automatically delivered to all scopes inside self.

pub fn force_cancel(self: Pin<&mut Self>)

Cancels all the tasks in the scope forcibly. Tasks within the scope enter a mercy period. They can do the last cleanup before exitting but will be automatically stopped at the next yield.

Tasks should shorten the mercy period as short as possible by introducing a cancellation point regularly, because it’s a kind of violation of Structured Concurrency (children are outliving the dropped parent).

Trait Implementations

impl<Fut, Joiner> FusedFuture for ScopeFuture<Fut, Joiner>

where Fut: Future, Joiner: Future<Output = ()>,

fn is_terminated(&self) -> bool

Returns true if the underlying future should no longer be polled.

impl<Fut, Joiner> Future for ScopeFuture<Fut, Joiner>

where Fut: Future, Joiner: Future<Output = ()>,

type Output = Result<<Fut as Future>::Output, Canceled>

The type of value produced on completion.

fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output>

Attempts to resolve the future to a final value, registering the current task for wakeup if the value is not yet available.

impl<'pin, Fut, Joiner> Unpin for ScopeFuture<Fut, Joiner>

where Fut: Future, __ScopeFuture<'pin, Fut, Joiner>: Unpin,