Enum futures_util::future::TryMaybeDone

pub enum TryMaybeDone<Fut: TryFuture> {
    Future(Fut),
    Done(Fut::Ok),
    Gone,
}

A future that may have completed with an error.

This is created by the try_maybe_done() function.

Variants

Future(Fut)

A not-yet-completed future

Done(Fut::Ok)

The output of the completed future

Gone

The empty variant after the result of a TryMaybeDone has been taken using the take_output method, or if the future returned an error.

Implementations

impl<Fut: TryFuture> TryMaybeDone<Fut>

pub fn output_mut(self: Pin<&mut Self>) -> Option<&mut Fut::Ok>

Returns an Option containing a mutable reference to the output of the future. The output of this method will be Some if and only if the inner future has completed successfully and take_output has not yet been called.

pub fn take_output(self: Pin<&mut Self>) -> Option<Fut::Ok>

Attempt to take the output of a TryMaybeDone without driving it towards completion.

Trait Implementations

impl<Fut: Debug + TryFuture> Debug for TryMaybeDone<Fut>

where Fut::Ok: Debug,

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<Fut: TryFuture> FusedFuture for TryMaybeDone<Fut>

fn is_terminated(&self) -> bool

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

impl<Fut: TryFuture> Future for TryMaybeDone<Fut>

type Output = Result<(), <Fut as TryFuture>::Error>

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<Fut: TryFuture + Unpin> Unpin for TryMaybeDone<Fut>