[][src]Struct futures_util::stream::futures_unordered::FuturesUnordered

#[must_use = "streams do nothing unless polled"]
pub struct FuturesUnordered<Fut> { /* fields omitted */ }

A set of futures which may complete in any order.

This structure is optimized to manage a large number of futures. Futures managed by FuturesUnordered will only be polled when they generate wake-up notifications. This reduces the required amount of work needed to poll large numbers of futures.

FuturesUnordered can be filled by collecting an iterator of futures into a FuturesUnordered, or by pushing futures onto an existing FuturesUnordered. When new futures are added, poll_next must be called in order to begin receiving wake-ups for new futures.

Note that you can create a ready-made FuturesUnordered via the collect method, or you can start with an empty set with the FuturesUnordered::new constructor.

Methods

impl<Fut: Future> FuturesUnordered<Fut>[src]

pub fn new() -> FuturesUnordered<Fut>[src]

Constructs a new, empty FuturesUnordered.

The returned FuturesUnordered does not contain any futures. In this state, FuturesUnordered::poll_next will return Poll::Ready(None).

impl<Fut> FuturesUnordered<Fut>[src]

pub fn len(&self) -> usize[src]

Returns the number of futures contained in the set.

This represents the total number of in-flight futures.

pub fn is_empty(&self) -> bool[src]

Returns true if the set contains no futures.

pub fn push(&mut self, future: Fut)[src]

Push a future into the set.

This method adds the given future to the set. This method will not call poll on the submitted future. The caller must ensure that FuturesUnordered::poll_next is called in order to receive wake-up notifications for the given future.

Important traits for IterMut<'a, Fut>
pub fn iter_mut(&mut self) -> IterMut<Fut> where
    Fut: Unpin
[src]

Returns an iterator that allows modifying each future in the set.

Important traits for IterPinMut<'a, Fut>
pub fn iter_pin_mut<'a>(self: Pin<&'a mut Self>) -> IterPinMut<'a, Fut>[src]

Returns an iterator that allows modifying each future in the set.

Trait Implementations

impl<Fut> Drop for FuturesUnordered<Fut>[src]

impl<Fut> Unpin for FuturesUnordered<Fut>[src]

impl<Fut: Sync> Sync for FuturesUnordered<Fut>[src]

impl<Fut: Future> Default for FuturesUnordered<Fut>[src]

impl<Fut: Send> Send for FuturesUnordered<Fut>[src]

impl<Fut> Debug for FuturesUnordered<Fut>[src]

impl<Fut: Future> FromIterator<Fut> for FuturesUnordered<Fut>[src]

impl<Fut: Future> Stream for FuturesUnordered<Fut>[src]

type Item = Fut::Output

Values yielded by the stream.

impl<Fut: Future> FusedStream for FuturesUnordered<Fut>[src]

impl<'a> Spawn for FuturesUnordered<FutureObj<'a, ()>>[src]

default fn status(&self) -> Result<(), SpawnError>[src]

Determines whether the executor is able to spawn new tasks. Read more

impl<'a> LocalSpawn for FuturesUnordered<LocalFutureObj<'a, ()>>[src]

default fn status_local(&self) -> Result<(), SpawnError>[src]

Determines whether the executor is able to spawn new tasks. Read more

Blanket Implementations

impl<T> StreamExt for T where
    T: Stream + ?Sized
[src]

Important traits for Next<'_, St>
fn next(&mut self) -> Next<Self> where
    Self: Sized + Unpin
[src]

Creates a future that resolves to the next item in the stream. Read more

Important traits for StreamFuture<St>
fn into_future(self) -> StreamFuture<Self> where
    Self: Sized + Unpin
[src]

Converts this stream into a future of (next_item, tail_of_stream). If the stream terminates, then the next item is None. Read more

fn map<T, F>(self, f: F) -> Map<Self, F> where
    F: FnMut(Self::Item) -> T,
    Self: Sized
[src]

Maps this stream's items to a different type, returning a new stream of the resulting type. Read more

fn filter<Fut, F>(self, f: F) -> Filter<Self, Fut, F> where
    F: FnMut(&Self::Item) -> Fut,
    Fut: Future<Output = bool>,
    Self: Sized
[src]

Filters the values produced by this stream according to the provided asynchronous predicate. Read more

fn filter_map<Fut, T, F>(self, f: F) -> FilterMap<Self, Fut, F> where
    F: FnMut(Self::Item) -> Fut,
    Fut: Future<Output = Option<T>>,
    Self: Sized
[src]

Filters the values produced by this stream while simultaneously mapping them to a different type according to the provided asynchronous closure. Read more

fn then<Fut, F>(self, f: F) -> Then<Self, Fut, F> where
    F: FnMut(Self::Item) -> Fut,
    Fut: Future,
    Self: Sized
[src]

Computes from this stream's items new items of a different type using an asynchronous closure. Read more

Important traits for Collect<St, C>
fn collect<C: Default + Extend<Self::Item>>(self) -> Collect<Self, C> where
    Self: Sized
[src]

Collect all of the values of this stream into a vector, returning a future representing the result of that computation. Read more

Important traits for Concat<St>
fn concat(self) -> Concat<Self> where
    Self: Sized,
    Self::Item: Extend<<Self::Item as IntoIterator>::Item> + IntoIterator + Default
[src]

Concatenate all items of a stream into a single extendable destination, returning a future representing the end result. Read more

Important traits for Fold<St, Fut, T, F>
fn fold<T, Fut, F>(self, init: T, f: F) -> Fold<Self, Fut, T, F> where
    F: FnMut(T, Self::Item) -> Fut,
    Fut: Future<Output = T>,
    Self: Sized
[src]

Execute an accumulating asynchronous computation over a stream, collecting all the values into one final result. Read more

fn flatten(self) -> Flatten<Self> where
    Self::Item: Stream,
    Self: Sized
[src]

Flattens a stream of streams into just one continuous stream. Read more

fn skip_while<Fut, F>(self, f: F) -> SkipWhile<Self, Fut, F> where
    F: FnMut(&Self::Item) -> Fut,
    Fut: Future<Output = bool>,
    Self: Sized
[src]

Skip elements on this stream while the provided asynchronous predicate resolves to true. Read more

fn take_while<Fut, F>(self, f: F) -> TakeWhile<Self, Fut, F> where
    F: FnMut(&Self::Item) -> Fut,
    Fut: Future<Output = bool>,
    Self: Sized
[src]

Take elements from this stream while the provided asynchronous predicate resolves to true. Read more

Important traits for ForEach<St, Fut, F>
fn for_each<Fut, F>(self, f: F) -> ForEach<Self, Fut, F> where
    F: FnMut(Self::Item) -> Fut,
    Fut: Future<Output = ()>,
    Self: Sized
[src]

Runs this stream to completion, executing the provided asynchronous closure for each element on the stream. Read more

Important traits for ForEachConcurrent<St, Fut, F>
fn for_each_concurrent<Fut, F>(
    self,
    limit: impl Into<Option<usize>>,
    f: F
) -> ForEachConcurrent<Self, Fut, F> where
    F: FnMut(Self::Item) -> Fut,
    Fut: Future<Output = ()>,
    Self: Sized
[src]

Runs this stream to completion, executing the provided asynchronous closure for each element on the stream concurrently as elements become available. Read more

fn take(self, n: u64) -> Take<Self> where
    Self: Sized
[src]

Creates a new stream of at most n items of the underlying stream. Read more

fn skip(self, n: u64) -> Skip<Self> where
    Self: Sized
[src]

Creates a new stream which skips n items of the underlying stream. Read more

fn fuse(self) -> Fuse<Self> where
    Self: Sized
[src]

Fuse a stream such that poll_next will never again be called once it has finished. This method can be used t turn any Stream into a FusedStream. Read more

Important traits for &'_ mut I
fn by_ref(&mut self) -> &mut Self where
    Self: Sized
[src]

Borrows a stream, rather than consuming it. Read more

fn catch_unwind(self) -> CatchUnwind<Self> where
    Self: Sized + UnwindSafe
[src]

Catches unwinding panics while polling the stream. Read more

Important traits for Pin<P>
fn boxed(self) -> Pin<Box<Self>> where
    Self: Sized
[src]

Wrap the stream in a Box, pinning it.

fn buffered(self, n: usize) -> Buffered<Self> where
    Self::Item: Future,
    Self: Sized
[src]

An adaptor for creating a buffered list of pending futures. Read more

fn buffer_unordered(self, n: usize) -> BufferUnordered<Self> where
    Self::Item: Future,
    Self: Sized
[src]

An adaptor for creating a buffered list of pending futures (unordered). Read more

fn zip<St>(self, other: St) -> Zip<Self, St> where
    St: Stream,
    Self: Sized
[src]

An adapter for zipping two streams together. Read more

fn chain<St>(self, other: St) -> Chain<Self, St> where
    St: Stream<Item = Self::Item>,
    Self: Sized
[src]

Adapter for chaining two stream. Read more

fn peekable(self) -> Peekable<Self> where
    Self: Sized
[src]

Creates a new stream which exposes a peek method. Read more

fn chunks(self, capacity: usize) -> Chunks<Self> where
    Self: Sized
[src]

An adaptor for chunking up items of the stream inside a vector. Read more

fn select<St>(self, other: St) -> Select<Self, St> where
    St: Stream<Item = Self::Item>,
    Self: Sized
[src]

This combinator will attempt to pull items from both streams. Each stream will be polled in a round-robin fashion, and whenever a stream is ready to yield an item that item is yielded. Read more

Important traits for Forward<St, Si>
fn forward<S>(self, sink: S) -> Forward<Self, S> where
    S: Sink<Self::Ok>,
    Self: TryStream<Error = S::SinkError> + Sized
[src]

A future that completes after the given stream has been fully processed into the sink and the sink has been flushed and closed. Read more

fn split<Item>(self) -> (SplitSink<Self, Item>, SplitStream<Self>) where
    Self: Sink<Item> + Sized
[src]

Splits this Stream + Sink object into separate Stream and Sink objects. Read more

fn inspect<F>(self, f: F) -> Inspect<Self, F> where
    F: FnMut(&Self::Item),
    Self: Sized
[src]

Do something with each item of this stream, afterwards passing it on. Read more

Important traits for Either<L, R>
fn left_stream<B>(self) -> Either<Self, B> where
    B: Stream<Item = Self::Item>,
    Self: Sized
[src]

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

Important traits for Either<L, R>
fn right_stream<B>(self) -> Either<B, Self> where
    B: Stream<Item = Self::Item>,
    Self: Sized
[src]

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

fn poll_next_unpin(&mut self, cx: &mut Context) -> Poll<Option<Self::Item>> where
    Self: Unpin + Sized
[src]

A convenience method for calling Stream::poll_next on Unpin stream types. Read more

Important traits for SelectNextSome<'a, St>
fn select_next_some(&mut self) -> SelectNextSome<Self> where
    Self: Sized + Unpin + FusedStream
[src]

Returns a Future that resolves when the next item in this stream is ready. Read more

impl<S> TryStreamExt for S where
    S: TryStream
[src]

fn err_into<E>(self) -> ErrInto<Self, E> where
    Self: Sized,
    Self::Error: Into<E>, 
[src]

Wraps the current stream in a new stream which converts the error type into the one provided. Read more

fn map_ok<T, F>(self, f: F) -> MapOk<Self, F> where
    Self: Sized,
    F: FnMut(Self::Ok) -> T, 
[src]

Wraps the current stream in a new stream which maps the success value using the provided closure. Read more

fn map_err<E, F>(self, f: F) -> MapErr<Self, F> where
    Self: Sized,
    F: FnMut(Self::Error) -> E, 
[src]

Wraps the current stream in a new stream which maps the error value using the provided closure. Read more

fn into_stream(self) -> IntoStream<Self> where
    Self: Sized
[src]

Wraps a TryStream into a type that implements Stream Read more

Important traits for TryNext<'_, St>
fn try_next(&mut self) -> TryNext<Self> where
    Self: Sized + Unpin
[src]

Creates a future that attempts to resolve the next item in the stream. If an error is encountered before the next item, the error is returned instead. Read more

Important traits for TryForEach<St, Fut, F>
fn try_for_each<Fut, F>(self, f: F) -> TryForEach<Self, Fut, F> where
    F: FnMut(Self::Ok) -> Fut,
    Fut: TryFuture<Ok = (), Error = Self::Error>,
    Self: Sized
[src]

Attempts to run this stream to completion, executing the provided asynchronous closure for each element on the stream. Read more

fn try_skip_while<Fut, F>(self, f: F) -> TrySkipWhile<Self, Fut, F> where
    F: FnMut(&Self::Ok) -> Fut,
    Fut: TryFuture<Ok = bool, Error = Self::Error>,
    Self: Sized
[src]

Skip elements on this stream while the provided asynchronous predicate resolves to true. Read more

Important traits for TryForEachConcurrent<St, Fut, F>
fn try_for_each_concurrent<Fut, F>(
    self,
    limit: impl Into<Option<usize>>,
    f: F
) -> TryForEachConcurrent<Self, Fut, F> where
    F: FnMut(Self::Ok) -> Fut,
    Fut: Future<Output = Result<(), Self::Error>>,
    Self: Sized
[src]

Attempts to run this stream to completion, executing the provided asynchronous closure for each element on the stream concurrently as elements become available, exiting as soon as an error occurs. Read more

Important traits for TryCollect<St, C>
fn try_collect<C: Default + Extend<Self::Ok>>(self) -> TryCollect<Self, C> where
    Self: Sized
[src]

Attempt to Collect all of the values of this stream into a vector, returning a future representing the result of that computation. Read more

fn try_filter_map<Fut, F, T>(self, f: F) -> TryFilterMap<Self, Fut, F> where
    Fut: TryFuture<Ok = Option<T>, Error = Self::Error>,
    F: FnMut(Self::Ok) -> Fut,
    Self: Sized
[src]

Attempt to filter the values produced by this stream while simultaneously mapping them to a different type according to the provided asynchronous closure. Read more

Important traits for TryFold<St, Fut, T, F>
fn try_fold<T, Fut, F>(self, init: T, f: F) -> TryFold<Self, Fut, T, F> where
    F: FnMut(T, Self::Ok) -> Fut,
    Fut: TryFuture<Ok = T, Error = Self::Error>,
    Self: Sized
[src]

Attempt to execute an accumulating asynchronous computation over a stream, collecting all the values into one final result. Read more

Important traits for TryConcat<St>
fn try_concat(self) -> TryConcat<Self> where
    Self: Sized,
    Self::Ok: Extend<<Self::Ok as IntoIterator>::Item> + IntoIterator + Default
[src]

Attempt to concatenate all items of a stream into a single extendable destination, returning a future representing the end result. Read more

fn try_buffer_unordered(self, n: usize) -> TryBufferUnordered<Self> where
    Self::Ok: TryFuture<Error = Self::Error>,
    Self: Sized
[src]

Attempt to execute several futures from a stream concurrently. Read more

fn try_poll_next_unpin(
    &mut self,
    cx: &mut Context
) -> Poll<Option<Result<Self::Ok, Self::Error>>> where
    Self: Unpin
[src]

A convenience method for calling [TryStream::poll_next_unpin] on Unpin stream types. Read more

Important traits for Compat<R>
fn compat(self) -> Compat<Self> where
    Self: Sized + Unpin
[src]

Wraps a TryStream into a stream compatible with libraries using futures 0.1 Stream. Requires the compat feature to be enabled. ``` #![feature(async_await, await_macro, futures_api)] use futures::future::{FutureExt, TryFutureExt}; # let (tx, rx) = futures::channel::oneshot::channel(); Read more

fn into_async_read(self) -> IntoAsyncRead<Self> where
    Self: Sized + TryStreamExt<Error = Error> + Unpin,
    Self::Ok: AsRef<[u8]>, 
[src]

Adapter that converts this stream into an [AsyncRead]. Read more

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<S, T, E> TryStream for S where
    S: Stream<Item = Result<T, E>>, 
[src]

type Ok = T

The type of successful values yielded by this future

type Error = E

The type of failures yielded by this future