Struct futures_util::stream::Empty
source · pub struct Empty<T> { /* private fields */ }Expand description
Stream for the empty function.
Trait Implementations§
source§impl<T> FusedStream for Empty<T>
impl<T> FusedStream for Empty<T>
source§fn is_terminated(&self) -> bool
fn is_terminated(&self) -> bool
Returns
true if the stream should no longer be polled.source§impl<T> Stream for Empty<T>
impl<T> Stream for Empty<T>
impl<T> Unpin for Empty<T>
Auto Trait Implementations§
impl<T> RefUnwindSafe for Empty<T>where T: RefUnwindSafe,
impl<T> Send for Empty<T>where T: Send,
impl<T> Sync for Empty<T>where T: Sync,
impl<T> UnwindSafe for Empty<T>where T: UnwindSafe,
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> StreamExt for Twhere
T: Stream + ?Sized,
impl<T> StreamExt for Twhere T: Stream + ?Sized,
source§fn next(&mut self) -> Next<'_, Self> ⓘwhere
Self: Unpin,
fn next(&mut self) -> Next<'_, Self> ⓘwhere Self: Unpin,
Creates a future that resolves to the next item in the stream. Read more
source§fn into_future(self) -> StreamFuture<Self> ⓘwhere
Self: Sized + Unpin,
fn into_future(self) -> StreamFuture<Self> ⓘwhere Self: Sized + Unpin,
source§fn map<T, F>(self, f: F) -> Map<Self, F>where
F: FnMut(Self::Item) -> T,
Self: Sized,
fn map<T, F>(self, f: F) -> Map<Self, F>where F: FnMut(Self::Item) -> T, Self: Sized,
Maps this stream’s items to a different type, returning a new stream of
the resulting type. Read more
source§fn enumerate(self) -> Enumerate<Self>where
Self: Sized,
fn enumerate(self) -> Enumerate<Self>where Self: Sized,
Creates a stream which gives the current iteration count as well as
the next value. Read more
source§fn filter<Fut, F>(self, f: F) -> Filter<Self, Fut, F>where
F: FnMut(&Self::Item) -> Fut,
Fut: Future<Output = bool>,
Self: Sized,
fn filter<Fut, F>(self, f: F) -> Filter<Self, Fut, F>where F: FnMut(&Self::Item) -> Fut, Fut: Future<Output = bool>, Self: Sized,
Filters the values produced by this stream according to the provided
asynchronous predicate. Read more
source§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,
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,
Filters the values produced by this stream while simultaneously mapping
them to a different type according to the provided asynchronous closure. Read more
source§fn then<Fut, F>(self, f: F) -> Then<Self, Fut, F>where
F: FnMut(Self::Item) -> Fut,
Fut: Future,
Self: Sized,
fn then<Fut, F>(self, f: F) -> Then<Self, Fut, F>where F: FnMut(Self::Item) -> Fut, Fut: Future, Self: Sized,
Computes from this stream’s items new items of a different type using
an asynchronous closure. Read more
source§fn collect<C: Default + Extend<Self::Item>>(self) -> Collect<Self, C> ⓘwhere
Self: Sized,
fn collect<C: Default + Extend<Self::Item>>(self) -> Collect<Self, C> ⓘwhere Self: Sized,
Transforms a stream into a collection, returning a
future representing the result of that computation. Read more
source§fn unzip<A, B, FromA, FromB>(self) -> Unzip<Self, FromA, FromB> ⓘwhere
FromA: Default + Extend<A>,
FromB: Default + Extend<B>,
Self: Sized + Stream<Item = (A, B)>,
fn unzip<A, B, FromA, FromB>(self) -> Unzip<Self, FromA, FromB> ⓘwhere FromA: Default + Extend<A>, FromB: Default + Extend<B>, Self: Sized + Stream<Item = (A, B)>,
Converts a stream of pairs into a future, which
resolves to pair of containers. Read more
source§fn concat(self) -> Concat<Self> ⓘwhere
Self: Sized,
Self::Item: Extend<<<Self as Stream>::Item as IntoIterator>::Item> + IntoIterator + Default,
fn concat(self) -> Concat<Self> ⓘwhere Self: Sized, Self::Item: Extend<<<Self as Stream>::Item as IntoIterator>::Item> + IntoIterator + Default,
Concatenate all items of a stream into a single extendable
destination, returning a future representing the end result. Read more
source§fn count(self) -> Count<Self> ⓘwhere
Self: Sized,
fn count(self) -> Count<Self> ⓘwhere Self: Sized,
Drives the stream to completion, counting the number of items. Read more
source§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,
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,
Execute an accumulating asynchronous computation over a stream,
collecting all the values into one final result. Read more
source§fn any<Fut, F>(self, f: F) -> Any<Self, Fut, F> ⓘwhere
F: FnMut(Self::Item) -> Fut,
Fut: Future<Output = bool>,
Self: Sized,
fn any<Fut, F>(self, f: F) -> Any<Self, Fut, F> ⓘwhere F: FnMut(Self::Item) -> Fut, Fut: Future<Output = bool>, Self: Sized,
Execute predicate over asynchronous stream, and return
true if any element in stream satisfied a predicate. Read moresource§fn all<Fut, F>(self, f: F) -> All<Self, Fut, F> ⓘwhere
F: FnMut(Self::Item) -> Fut,
Fut: Future<Output = bool>,
Self: Sized,
fn all<Fut, F>(self, f: F) -> All<Self, Fut, F> ⓘwhere F: FnMut(Self::Item) -> Fut, Fut: Future<Output = bool>, Self: Sized,
Execute predicate over asynchronous stream, and return
true if all element in stream satisfied a predicate. Read moresource§fn flatten(self) -> Flatten<Self>where
Self::Item: Stream,
Self: Sized,
fn flatten(self) -> Flatten<Self>where Self::Item: Stream, Self: Sized,
Flattens a stream of streams into just one continuous stream. Read more
source§fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>where
F: FnMut(Self::Item) -> U,
U: Stream,
Self: Sized,
fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>where F: FnMut(Self::Item) -> U, U: Stream, Self: Sized,
source§fn scan<S, B, Fut, F>(self, initial_state: S, f: F) -> Scan<Self, S, Fut, F>where
F: FnMut(&mut S, Self::Item) -> Fut,
Fut: Future<Output = Option<B>>,
Self: Sized,
fn scan<S, B, Fut, F>(self, initial_state: S, f: F) -> Scan<Self, S, Fut, F>where F: FnMut(&mut S, Self::Item) -> Fut, Fut: Future<Output = Option<B>>, Self: Sized,
Combinator similar to
StreamExt::fold that holds internal state
and produces a new stream. Read moresource§fn skip_while<Fut, F>(self, f: F) -> SkipWhile<Self, Fut, F>where
F: FnMut(&Self::Item) -> Fut,
Fut: Future<Output = bool>,
Self: Sized,
fn skip_while<Fut, F>(self, f: F) -> SkipWhile<Self, Fut, F>where F: FnMut(&Self::Item) -> Fut, Fut: Future<Output = bool>, Self: Sized,
Skip elements on this stream while the provided asynchronous predicate
resolves to
true. Read moresource§fn take_while<Fut, F>(self, f: F) -> TakeWhile<Self, Fut, F>where
F: FnMut(&Self::Item) -> Fut,
Fut: Future<Output = bool>,
Self: Sized,
fn take_while<Fut, F>(self, f: F) -> TakeWhile<Self, Fut, F>where F: FnMut(&Self::Item) -> Fut, Fut: Future<Output = bool>, Self: Sized,
Take elements from this stream while the provided asynchronous predicate
resolves to
true. Read moresource§fn take_until<Fut>(self, fut: Fut) -> TakeUntil<Self, Fut>where
Fut: Future,
Self: Sized,
fn take_until<Fut>(self, fut: Fut) -> TakeUntil<Self, Fut>where Fut: Future, Self: Sized,
Take elements from this stream until the provided future resolves. Read more
source§fn for_each<Fut, F>(self, f: F) -> ForEach<Self, Fut, F> ⓘwhere
F: FnMut(Self::Item) -> Fut,
Fut: Future<Output = ()>,
Self: Sized,
fn for_each<Fut, F>(self, f: F) -> ForEach<Self, Fut, F> ⓘwhere F: FnMut(Self::Item) -> Fut, Fut: Future<Output = ()>, Self: Sized,
Runs this stream to completion, executing the provided asynchronous
closure for each element on the stream. Read more
source§fn take(self, n: usize) -> Take<Self>where
Self: Sized,
fn take(self, n: usize) -> Take<Self>where Self: Sized,
Creates a new stream of at most
n items of the underlying stream. Read moresource§fn skip(self, n: usize) -> Skip<Self>where
Self: Sized,
fn skip(self, n: usize) -> Skip<Self>where Self: Sized,
Creates a new stream which skips
n items of the underlying stream. Read moresource§fn zip<St>(self, other: St) -> Zip<Self, St>where
St: Stream,
Self: Sized,
fn zip<St>(self, other: St) -> Zip<Self, St>where St: Stream, Self: Sized,
An adapter for zipping two streams together. Read more
source§fn chain<St>(self, other: St) -> Chain<Self, St>where
St: Stream<Item = Self::Item>,
Self: Sized,
fn chain<St>(self, other: St) -> Chain<Self, St>where St: Stream<Item = Self::Item>, Self: Sized,
Adapter for chaining two streams. Read more
source§fn peekable(self) -> Peekable<Self>where
Self: Sized,
fn peekable(self) -> Peekable<Self>where Self: Sized,
Creates a new stream which exposes a
peek method. Read moresource§fn inspect<F>(self, f: F) -> Inspect<Self, F>where
F: FnMut(&Self::Item),
Self: Sized,
fn inspect<F>(self, f: F) -> Inspect<Self, F>where F: FnMut(&Self::Item), Self: Sized,
Do something with each item of this stream, afterwards passing it on. Read more
source§fn right_stream<B>(self) -> Either<B, Self> ⓘwhere
B: Stream<Item = Self::Item>,
Self: Sized,
fn right_stream<B>(self) -> Either<B, Self> ⓘwhere B: Stream<Item = Self::Item>, Self: Sized,
source§fn poll_next_unpin(&mut self, cx: &mut Context<'_>) -> Poll<Option<Self::Item>>where
Self: Unpin,
fn poll_next_unpin(&mut self, cx: &mut Context<'_>) -> Poll<Option<Self::Item>>where Self: Unpin,
A convenience method for calling
Stream::poll_next on Unpin
stream types.source§fn select_next_some(&mut self) -> SelectNextSome<'_, Self> ⓘwhere
Self: Unpin + FusedStream,
fn select_next_some(&mut self) -> SelectNextSome<'_, Self> ⓘwhere Self: Unpin + FusedStream,
source§impl<S> TryStreamExt for Swhere
S: TryStream + ?Sized,
impl<S> TryStreamExt for Swhere S: TryStream + ?Sized,
source§fn err_into<E>(self) -> ErrInto<Self, E>where
Self: Sized,
Self::Error: Into<E>,
fn err_into<E>(self) -> ErrInto<Self, E>where Self: Sized, Self::Error: Into<E>,
Wraps the current stream in a new stream which converts the error type
into the one provided. Read more
source§fn map_ok<T, F>(self, f: F) -> MapOk<Self, F>where
Self: Sized,
F: FnMut(Self::Ok) -> T,
fn map_ok<T, F>(self, f: F) -> MapOk<Self, F>where Self: Sized, F: FnMut(Self::Ok) -> T,
Wraps the current stream in a new stream which maps the success value
using the provided closure. Read more
source§fn map_err<E, F>(self, f: F) -> MapErr<Self, F>where
Self: Sized,
F: FnMut(Self::Error) -> E,
fn map_err<E, F>(self, f: F) -> MapErr<Self, F>where Self: Sized, F: FnMut(Self::Error) -> E,
Wraps the current stream in a new stream which maps the error value
using the provided closure. Read more
source§fn and_then<Fut, F>(self, f: F) -> AndThen<Self, Fut, F>where
F: FnMut(Self::Ok) -> Fut,
Fut: TryFuture<Error = Self::Error>,
Self: Sized,
fn and_then<Fut, F>(self, f: F) -> AndThen<Self, Fut, F>where F: FnMut(Self::Ok) -> Fut, Fut: TryFuture<Error = Self::Error>, Self: Sized,
Chain on a computation for when a value is ready, passing the successful
results to the provided closure
f. Read moresource§fn or_else<Fut, F>(self, f: F) -> OrElse<Self, Fut, F>where
F: FnMut(Self::Error) -> Fut,
Fut: TryFuture<Ok = Self::Ok>,
Self: Sized,
fn or_else<Fut, F>(self, f: F) -> OrElse<Self, Fut, F>where F: FnMut(Self::Error) -> Fut, Fut: TryFuture<Ok = Self::Ok>, Self: Sized,
Chain on a computation for when an error happens, passing the
erroneous result to the provided closure
f. Read moresource§fn inspect_ok<F>(self, f: F) -> InspectOk<Self, F>where
F: FnMut(&Self::Ok),
Self: Sized,
fn inspect_ok<F>(self, f: F) -> InspectOk<Self, F>where F: FnMut(&Self::Ok), Self: Sized,
Do something with the success value of this stream, afterwards passing
it on. Read more
source§fn inspect_err<F>(self, f: F) -> InspectErr<Self, F>where
F: FnMut(&Self::Error),
Self: Sized,
fn inspect_err<F>(self, f: F) -> InspectErr<Self, F>where F: FnMut(&Self::Error), Self: Sized,
Do something with the error value of this stream, afterwards passing it on. Read more
source§fn into_stream(self) -> IntoStream<Self>where
Self: Sized,
fn into_stream(self) -> IntoStream<Self>where Self: Sized,
source§fn try_next(&mut self) -> TryNext<'_, Self> ⓘwhere
Self: Unpin,
fn try_next(&mut self) -> TryNext<'_, Self> ⓘwhere Self: Unpin,
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
source§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,
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,
Attempts to run this stream to completion, executing the provided
asynchronous closure for each element on the stream. Read more
source§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,
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,
Skip elements on this stream while the provided asynchronous predicate
resolves to
true. Read moresource§fn try_take_while<Fut, F>(self, f: F) -> TryTakeWhile<Self, Fut, F>where
F: FnMut(&Self::Ok) -> Fut,
Fut: TryFuture<Ok = bool, Error = Self::Error>,
Self: Sized,
fn try_take_while<Fut, F>(self, f: F) -> TryTakeWhile<Self, Fut, F>where F: FnMut(&Self::Ok) -> Fut, Fut: TryFuture<Ok = bool, Error = Self::Error>, Self: Sized,
Take elements on this stream while the provided asynchronous predicate
resolves to
true. Read moresource§fn try_collect<C: Default + Extend<Self::Ok>>(self) -> TryCollect<Self, C> ⓘwhere
Self: Sized,
fn try_collect<C: Default + Extend<Self::Ok>>(self) -> TryCollect<Self, C> ⓘwhere Self: Sized,
Attempt to transform a stream into a collection,
returning a future representing the result of that computation. Read more
source§fn try_filter<Fut, F>(self, f: F) -> TryFilter<Self, Fut, F>where
Fut: Future<Output = bool>,
F: FnMut(&Self::Ok) -> Fut,
Self: Sized,
fn try_filter<Fut, F>(self, f: F) -> TryFilter<Self, Fut, F>where Fut: Future<Output = bool>, F: FnMut(&Self::Ok) -> Fut, Self: Sized,
Attempt to filter the values produced by this stream according to the
provided asynchronous closure. Read more
source§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,
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,
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
source§fn try_flatten(self) -> TryFlatten<Self>where
Self::Ok: TryStream,
<Self::Ok as TryStream>::Error: From<Self::Error>,
Self: Sized,
fn try_flatten(self) -> TryFlatten<Self>where Self::Ok: TryStream, <Self::Ok as TryStream>::Error: From<Self::Error>, Self: Sized,
Flattens a stream of streams into just one continuous stream. Read more
source§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,
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,
Attempt to execute an accumulating asynchronous computation over a
stream, collecting all the values into one final result. Read more
source§fn try_concat(self) -> TryConcat<Self> ⓘwhere
Self: Sized,
Self::Ok: Extend<<<Self as TryStream>::Ok as IntoIterator>::Item> + IntoIterator + Default,
fn try_concat(self) -> TryConcat<Self> ⓘwhere Self: Sized, Self::Ok: Extend<<<Self as TryStream>::Ok as IntoIterator>::Item> + IntoIterator + Default,
Attempt to concatenate all items of a stream into a single
extendable destination, returning a future representing the end result. Read more
source§fn try_poll_next_unpin(
&mut self,
cx: &mut Context<'_>
) -> Poll<Option<Result<Self::Ok, Self::Error>>>where
Self: Unpin,
fn try_poll_next_unpin( &mut self, cx: &mut Context<'_> ) -> Poll<Option<Result<Self::Ok, Self::Error>>>where Self: Unpin,
A convenience method for calling
TryStream::try_poll_next on Unpin
stream types.source§fn try_all<Fut, F>(self, f: F) -> TryAll<Self, Fut, F>where
Self: Sized,
F: FnMut(Self::Ok) -> Fut,
Fut: Future<Output = bool>,
fn try_all<Fut, F>(self, f: F) -> TryAll<Self, Fut, F>where Self: Sized, F: FnMut(Self::Ok) -> Fut, Fut: Future<Output = bool>,
Attempt to execute a predicate over an asynchronous stream and evaluate if all items
satisfy the predicate. Exits early if an
Err is encountered or if an Ok item is found
that does not satisfy the predicate. Read moresource§fn try_any<Fut, F>(self, f: F) -> TryAny<Self, Fut, F>where
Self: Sized,
F: FnMut(Self::Ok) -> Fut,
Fut: Future<Output = bool>,
fn try_any<Fut, F>(self, f: F) -> TryAny<Self, Fut, F>where Self: Sized, F: FnMut(Self::Ok) -> Fut, Fut: Future<Output = bool>,
Attempt to execute a predicate over an asynchronous stream and evaluate if any items
satisfy the predicate. Exits early if an
Err is encountered or if an Ok item is found
that satisfies the predicate. Read more