[−][src]Enum futures::future::MaybeDone

pub enum MaybeDone<Fut> where
    Fut: Future,  {
    Future(Fut),
    Done(<Fut as Future>::Output),
    Gone,
}

A future that may have completed.

This is created by the maybe_done() function.

Variants

Future(Fut)

A not-yet-completed future

Done(<Fut as Future>::Output)

The output of the completed future

Gone

The empty variant after the result of a MaybeDone has been taken using the take_output method.

Methods

impl<Fut> MaybeDone<Fut> where
    Fut: Future, [src]

pub fn output_mut(
    self: Pin<&'a mut MaybeDone<Fut>>
) -> Option<&'a mut <Fut as Future>::Output>[src]

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 been completed and take_output has not yet been called.

pub fn take_output(
    self: Pin<&mut MaybeDone<Fut>>
) -> Option<<Fut as Future>::Output>[src]

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

Trait Implementations

impl<Fut> Unpin for MaybeDone<Fut> where
    Fut: Unpin + Future, [src]

impl<Fut> Future for MaybeDone<Fut> where
    Fut: Future, [src]

type Output = ()

🔬 This is a nightly-only experimental API. (futures_api)

futures in libcore are unstable

The type of value produced on completion.

impl<Fut> FusedFuture for MaybeDone<Fut> where
    Fut: Future, [src]

impl<Fut> Debug for MaybeDone<Fut> where
    Fut: Debug + Future,
    <Fut as Future>::Output: Debug, [src]

Auto Trait Implementations

impl<Fut> Send for MaybeDone<Fut> where
    Fut: Send,
    <Fut as Future>::Output: Send, 

impl<Fut> Sync for MaybeDone<Fut> where
    Fut: Sync,
    <Fut as Future>::Output: Sync, 

Blanket Implementations

impl<T> From for T[src]

impl<T, U> Into for T where
    U: From<T>, [src]

impl<T, U> TryFrom for T where
    U: Into<T>, [src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T> Borrow for T where
    T: ?Sized, [src]

impl<T> BorrowMut for T where
    T: ?Sized, [src]

impl<T, U> TryInto for T where
    U: TryFrom<T>, [src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

impl<T> Any for T where
    T: 'static + ?Sized, [src]

impl<T> FutureExt for T where
    T: Future + ?Sized, [src]

ⓘImportant traits for Map<Fut, F>
default fn map<U, F>(self, f: F) -> Map<Self, F> where
    F: FnOnce(Self::Output) -> U, [src]

Map this future's output to a different type, returning a new future of the resulting type. Read more

ⓘImportant traits for Then<Fut1, Fut2, F>
default fn then<Fut, F>(self, f: F) -> Then<Self, Fut, F> where
    F: FnOnce(Self::Output) -> Fut,
    Fut: Future, [src]

Chain on a computation for when a future finished, passing the result of the future to the provided closure f. Read more

default fn into_stream(self) -> IntoStream<Self>[src]

Convert this future into a single element stream. Read more

ⓘImportant traits for Flatten<Fut>
default fn flatten(self) -> Flatten<Self> where
    Self::Output: Future, [src]

Flatten the execution of this future when the successful result of this future is itself another future. Read more

default fn flatten_stream(self) -> FlattenStream<Self> where
    Self::Output: Stream, [src]

Flatten the execution of this future when the successful result of this future is a stream. Read more

ⓘImportant traits for Fuse<Fut>
default fn fuse(self) -> Fuse<Self>[src]

Fuse a future such that poll will never again be called once it has completed. This method can be used to turn any Future into a FusedFuture. Read more

ⓘImportant traits for Inspect<Fut, F>
default fn inspect<F>(self, f: F) -> Inspect<Self, F> where
    F: FnOnce(&Self::Output), [src]

Do something with the output of a future before passing it on. Read more

ⓘImportant traits for CatchUnwind<Fut>
default fn catch_unwind(self) -> CatchUnwind<Self> where
    Self: UnwindSafe, [src]

Catches unwinding panics while polling the future. Read more

ⓘImportant traits for Shared<Fut>
default fn shared(self) -> Shared<Self> where
    Self::Output: Clone, [src]

Create a cloneable handle to this future where all handles will resolve to the same result. Read more

default fn remote_handle(self) -> (Remote<Self>, RemoteHandle<Self::Output>)[src]

Turn this future into a future that yields () on completion and sends its output to another future on a separate task. Read more

ⓘImportant traits for Pin<P>
default fn boxed(self) -> Pin<Box<Self>>[src]

Wrap the future in a Box, pinning it.

ⓘImportant traits for UnitError<Fut>
default fn unit_error(self) -> UnitError<Self>[src]

Turns a Future into a TryFuture with Error = ().

default fn poll_unpin(&mut self, cx: &mut Context) -> Poll<Self::Output> where
    Self: Unpin, [src]

A convenience for calling Future::poll on Unpin future types.