Enum futures_util::future::MaybeDone
source · pub enum MaybeDone<Fut: Future> {
Future(Fut),
Done(Fut::Output),
Gone,
}
Expand description
A future that may have completed.
This is created by the maybe_done()
function.
Variants§
Future(Fut)
A not-yet-completed future
Done(Fut::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.
Implementations§
source§impl<Fut: Future> MaybeDone<Fut>
impl<Fut: Future> MaybeDone<Fut>
sourcepub fn output_mut(self: Pin<&mut Self>) -> Option<&mut Fut::Output>
pub fn output_mut(self: Pin<&mut Self>) -> Option<&mut Fut::Output>
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.
sourcepub fn take_output(self: Pin<&mut Self>) -> Option<Fut::Output>
pub fn take_output(self: Pin<&mut Self>) -> Option<Fut::Output>
Attempt to take the output of a MaybeDone
without driving it
towards completion.
Trait Implementations§
source§impl<Fut: Future> FusedFuture for MaybeDone<Fut>
impl<Fut: Future> FusedFuture for MaybeDone<Fut>
source§fn is_terminated(&self) -> bool
fn is_terminated(&self) -> bool
Returns
true
if the underlying future should no longer be polled.impl<Fut: Future + Unpin> Unpin for MaybeDone<Fut>
Auto Trait Implementations§
impl<Fut> Freeze for MaybeDone<Fut>
impl<Fut> RefUnwindSafe for MaybeDone<Fut>
impl<Fut> Send for MaybeDone<Fut>
impl<Fut> Sync for MaybeDone<Fut>
impl<Fut> UnwindSafe for MaybeDone<Fut>
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> FutureExt for T
impl<T> FutureExt for T
source§fn map<U, F>(self, f: F) -> Map<Self, F> ⓘ
fn map<U, F>(self, f: F) -> Map<Self, F> ⓘ
Map this future’s output to a different type, returning a new future of
the resulting type. Read more
source§fn map_into<U>(self) -> MapInto<Self, U> ⓘ
fn map_into<U>(self) -> MapInto<Self, U> ⓘ
Map this future’s output to a different type, returning a new future of
the resulting type. Read more
source§fn then<Fut, F>(self, f: F) -> Then<Self, Fut, F> ⓘ
fn then<Fut, F>(self, f: F) -> Then<Self, Fut, F> ⓘ
Chain on a computation for when a future finished, passing the result of
the future to the provided closure
f
. Read moresource§fn left_future<B>(self) -> Either<Self, B> ⓘ
fn left_future<B>(self) -> Either<Self, B> ⓘ
source§fn right_future<A>(self) -> Either<A, Self> ⓘ
fn right_future<A>(self) -> Either<A, Self> ⓘ
source§fn into_stream(self) -> IntoStream<Self>where
Self: Sized,
fn into_stream(self) -> IntoStream<Self>where
Self: Sized,
Convert this future into a single element stream. Read more
source§fn flatten(self) -> Flatten<Self> ⓘ
fn flatten(self) -> Flatten<Self> ⓘ
Flatten the execution of this future when the output of this
future is itself another future. Read more
source§fn flatten_stream(self) -> FlattenStream<Self>
fn flatten_stream(self) -> FlattenStream<Self>
Flatten the execution of this future when the successful result of this
future is a stream. Read more
source§fn fuse(self) -> Fuse<Self> ⓘwhere
Self: Sized,
fn fuse(self) -> Fuse<Self> ⓘwhere
Self: Sized,
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 moresource§fn inspect<F>(self, f: F) -> Inspect<Self, F> ⓘ
fn inspect<F>(self, f: F) -> Inspect<Self, F> ⓘ
Do something with the output of a future before passing it on. Read more
source§fn catch_unwind(self) -> CatchUnwind<Self> ⓘwhere
Self: Sized + UnwindSafe,
fn catch_unwind(self) -> CatchUnwind<Self> ⓘwhere
Self: Sized + UnwindSafe,
Catches unwinding panics while polling the future. Read more
Create a cloneable handle to this future where all handles will resolve
to the same result. Read more
source§fn remote_handle(self) -> (Remote<Self>, RemoteHandle<Self::Output>)where
Self: Sized,
fn remote_handle(self) -> (Remote<Self>, RemoteHandle<Self::Output>)where
Self: Sized,
Turn this future into a future that yields
()
on completion and sends
its output to another future on a separate task. Read moresource§fn boxed<'a>(self) -> BoxFuture<'a, Self::Output>
fn boxed<'a>(self) -> BoxFuture<'a, Self::Output>
Wrap the future in a Box, pinning it. Read more
source§fn boxed_local<'a>(self) -> LocalBoxFuture<'a, Self::Output>where
Self: Sized + 'a,
fn boxed_local<'a>(self) -> LocalBoxFuture<'a, Self::Output>where
Self: Sized + 'a,
Wrap the future in a Box, pinning it. Read more
source§fn unit_error(self) -> UnitError<Self> ⓘwhere
Self: Sized,
fn unit_error(self) -> UnitError<Self> ⓘwhere
Self: Sized,
Turns a
Future<Output = T>
into a
TryFuture<Ok = T, Error = ()
>.source§fn never_error(self) -> NeverError<Self> ⓘwhere
Self: Sized,
fn never_error(self) -> NeverError<Self> ⓘwhere
Self: Sized,
Turns a
Future<Output = T>
into a
TryFuture<Ok = T, Error = Never
>.source§impl<F> IntoFuture for Fwhere
F: Future,
impl<F> IntoFuture for Fwhere
F: Future,
§type IntoFuture = F
type IntoFuture = F
Which kind of future are we turning this into?
source§fn into_future(self) -> <F as IntoFuture>::IntoFuture
fn into_future(self) -> <F as IntoFuture>::IntoFuture
Creates a future from a value. Read more