async_utils::futures

Struct YieldToExecutorOnce

Source
pub struct YieldToExecutorOnce(/* private fields */);
Expand description

A future that yields to the executor only once.

This future returns [Poll::Pending] the first time it’s polled after waking the context waker. This effectively yields the currently running task to the executor, but puts it back in the executor’s ready task queue.

Example:

loop {
  let read = read_big_thing().await;

  while let Some(x) = read.next() {
    process_one_thing(x);
    YieldToExecutorOnce::new().await;
  }
}

Implementations§

Source§

impl YieldToExecutorOnce

Source

pub fn new() -> Self

Creates a new YieldToExecutorOnce.

Trait Implementations§

Source§

impl Default for YieldToExecutorOnce

Source§

fn default() -> YieldToExecutorOnce

Returns the “default value” for a type. Read more
Source§

impl FusedFuture for YieldToExecutorOnce

Source§

fn is_terminated(&self) -> bool

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

impl Future for YieldToExecutorOnce

Source§

type Output = ()

The type of value produced on completion.
Source§

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. Read more

Auto Trait Implementations§

Blanket Implementations§

Source§

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

Source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
Source§

impl<T> Borrow<T> for T
where T: ?Sized,

Source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
Source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

Source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
§

impl<T, D> Encode<Ambiguous1, D> for T
where D: ResourceDialect,

§

unsafe fn encode( self, _encoder: &mut Encoder<'_, D>, _offset: usize, _depth: Depth, ) -> Result<(), Error>

Encodes the object into the encoder’s buffers. Any handles stored in the object are swapped for Handle::INVALID. Read more
§

impl<T, D> Encode<Ambiguous2, D> for T
where D: ResourceDialect,

§

unsafe fn encode( self, _encoder: &mut Encoder<'_, D>, _offset: usize, _depth: Depth, ) -> Result<(), Error>

Encodes the object into the encoder’s buffers. Any handles stored in the object are swapped for Handle::INVALID. Read more
Source§

impl<T> From<T> for T

Source§

fn from(t: T) -> T

Returns the argument unchanged.

§

impl<F> FutureExt for F
where F: Future + ?Sized,

§

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

A convenience for calling Future::poll() on !Unpin types.
§

fn or<F>(self, other: F) -> Or<Self, F>
where Self: Sized, F: Future<Output = Self::Output>,

Returns the result of self or other future, preferring self if both are ready. Read more
§

fn race<F>(self, other: F) -> Race<Self, F>
where Self: Sized, F: Future<Output = Self::Output>,

Returns the result of self or other future, with no preference if both are ready. Read more
§

fn catch_unwind(self) -> CatchUnwind<Self>
where Self: Sized + UnwindSafe,

Catches panics while polling the future. Read more
§

fn boxed<'a>(self) -> Pin<Box<dyn Future<Output = Self::Output> + Send + 'a>>
where Self: Sized + Send + 'a,

Boxes the future and changes its type to dyn Future + Send + 'a. Read more
§

fn boxed_local<'a>(self) -> Pin<Box<dyn Future<Output = Self::Output> + 'a>>
where Self: Sized + 'a,

Boxes the future and changes its type to dyn Future + 'a. Read more
Source§

impl<T> FutureExt for T
where T: Future<Output = ()> + ?Sized,

Source§

fn replace_value<T>(self, value: T) -> ReplaceValue<Self, T>
where Self: Sized,

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

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

§

fn map<U, F>(self, f: F) -> Map<Self, F>
where F: FnOnce(Self::Output) -> U, Self: Sized,

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

fn map_into<U>(self) -> MapInto<Self, U>
where Self::Output: Into<U>, Self: Sized,

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

fn then<Fut, F>(self, f: F) -> Then<Self, Fut, F>
where F: FnOnce(Self::Output) -> Fut, Fut: Future, Self: Sized,

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

fn left_future<B>(self) -> Either<Self, B>
where B: Future<Output = Self::Output>, Self: Sized,

Wrap this future in an Either future, making it the left-hand variant of that Either. Read more
§

fn right_future<A>(self) -> Either<A, Self>
where A: Future<Output = Self::Output>, Self: Sized,

Wrap this future in an Either future, making it the right-hand variant of that Either. Read more
§

fn into_stream(self) -> IntoStream<Self>
where Self: Sized,

Convert this future into a single element stream. Read more
§

fn flatten(self) -> Flatten<Self>
where Self::Output: Future, Self: Sized,

Flatten the execution of this future when the output of this future is itself another future. Read more
§

fn flatten_stream(self) -> FlattenStream<Self>
where Self::Output: Stream, Self: Sized,

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

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 more
§

fn inspect<F>(self, f: F) -> Inspect<Self, F>
where F: FnOnce(&Self::Output), Self: Sized,

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

fn catch_unwind(self) -> CatchUnwind<Self>
where Self: Sized + UnwindSafe,

Catches unwinding panics while polling the future. Read more
§

fn shared(self) -> Shared<Self>
where Self: Sized, Self::Output: Clone,

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

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 more
§

fn boxed<'a>(self) -> Pin<Box<dyn Future<Output = Self::Output> + Send + 'a>>
where Self: Sized + Send + 'a,

Wrap the future in a Box, pinning it. Read more
§

fn boxed_local<'a>(self) -> Pin<Box<dyn Future<Output = Self::Output> + 'a>>
where Self: Sized + 'a,

Wrap the future in a Box, pinning it. Read more
§

fn unit_error(self) -> UnitError<Self>
where Self: Sized,

§

fn never_error(self) -> NeverError<Self>
where Self: Sized,

§

fn poll_unpin(&mut self, cx: &mut Context<'_>) -> Poll<Self::Output>
where Self: Unpin,

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

fn now_or_never(self) -> Option<Self::Output>
where Self: Sized,

Evaluates and consumes the future, returning the resulting output if the future is ready after the first call to Future::poll. Read more
§

impl<T> Instrument for T

§

fn instrument(self, span: Span) -> Instrumented<Self>

Instruments this type with the provided [Span], returning an Instrumented wrapper. Read more
§

fn in_current_span(self) -> Instrumented<Self>

Instruments this type with the current Span, returning an Instrumented wrapper. Read more
Source§

impl<T, U> Into<U> for T
where U: From<T>,

Source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Source§

impl<F> IntoFuture for F
where F: Future,

Source§

type Output = <F as Future>::Output

The output that the future will produce on completion.
Source§

type IntoFuture = F

Which kind of future are we turning this into?
Source§

fn into_future(self) -> <F as IntoFuture>::IntoFuture

Creates a future from a value. Read more
§

impl<T> Pointable for T

§

const ALIGN: usize = _

The alignment of pointer.
§

type Init = T

The type for initializers.
§

unsafe fn init(init: <T as Pointable>::Init) -> usize

Initializes a with the given initializer. Read more
§

unsafe fn deref<'a>(ptr: usize) -> &'a T

Dereferences the given pointer. Read more
§

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

Mutably dereferences the given pointer. Read more
§

unsafe fn drop(ptr: usize)

Drops the object pointed to by the given pointer. Read more
§

impl<F> TimeoutExt for F
where F: Future,

§

fn on_timeout<WT, OT>(self, time: WT, on_timeout: OT) -> OnTimeout<Self, OT>
where WT: WakeupTime, OT: FnOnce() -> Self::Output,

Wraps the future in a timeout, calling on_timeout to produce a result when the timeout occurs.
§

fn on_stalled<OS>( self, timeout: Duration, on_stalled: OS, ) -> OnStalled<Self, OS>
where OS: FnOnce() -> Self::Output,

Wraps the future in a stall-guard, calling on_stalled to produce a result when the future hasn’t been otherwise polled within the timeout. This is a heuristic - spurious wakeups will keep the detection from triggering, and moving all work to external tasks or threads with force the triggering early.
Source§

impl<T, U> TryFrom<U> for T
where U: Into<T>,

Source§

type Error = Infallible

The type returned in the event of a conversion error.
Source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
Source§

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

Source§

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

The type returned in the event of a conversion error.
Source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
§

impl<T> WithSubscriber for T

§

fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
where S: Into<Dispatch>,

Attaches the provided Subscriber to this type, returning a [WithDispatch] wrapper. Read more
§

fn with_current_subscriber(self) -> WithDispatch<Self>

Attaches the current default Subscriber to this type, returning a [WithDispatch] wrapper. Read more
Source§

impl<St> WithTag for St

Source§

fn tagged<T>(self, tag: T) -> Tagged<T, St>

Produce a new stream from this one which yields item tupled with a constant tag