Struct async_std::stream::Empty [−][src]
pub struct Empty<T> { /* fields omitted */ }A stream that doesn’t yield any items.
This stream is constructed by the empty function.
Trait Implementations
impl<T: Debug> Debug for Empty<T>[src][+]
fn fmt(&self, f: &mut Formatter<'_>) -> Result[src][−]
Formats the value using the given formatter. Read more
impl<T> Stream for Empty<T>[src][+]
type Item = T
Values yielded by the stream.
fn poll_next(
self: Pin<&mut Self>,
_: &mut Context<'_>
) -> Poll<Option<Self::Item>>[src][−]
self: Pin<&mut Self>,
_: &mut Context<'_>
) -> Poll<Option<Self::Item>>
Attempt to pull out the next value of this stream, registering the
current task for wakeup if the value is not yet available, and returning
None if the stream is exhausted. Read more
pub fn size_hint(&self) -> (usize, Option<usize>)[src][−]
Returns the bounds on the remaining length of the stream. Read more
Auto Trait Implementations
impl<T> RefUnwindSafe for Empty<T> where
T: RefUnwindSafe,
T: RefUnwindSafe,
impl<T> Send for Empty<T> where
T: Send,
T: Send,
impl<T> Sync for Empty<T> where
T: Sync,
T: Sync,
impl<T> Unpin for Empty<T> where
T: Unpin,
T: Unpin,
impl<T> UnwindSafe for Empty<T> where
T: UnwindSafe,
T: UnwindSafe,
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized, [src][+]
T: 'static + ?Sized,
pub fn type_id(&self) -> TypeId[src][−]
Gets the TypeId of self. Read more
impl<T> Borrow<T> for T where
T: ?Sized, [src][+]
T: ?Sized,
pub fn borrow(&self) -> &Tⓘ[src][−]
Immutably borrows from an owned value. Read more
impl<T> BorrowMut<T> for T where
T: ?Sized, [src][+]
T: ?Sized,
pub fn borrow_mut(&mut self) -> &mut Tⓘ[src][−]
Mutably borrows from an owned value. Read more
impl<T> From<T> for T[src][+]
impl<T, U> Into<U> for T where
U: From<T>, [src][+]
U: From<T>,
impl<S> StreamExt for S where
S: Stream + ?Sized, [src][+]
S: Stream + ?Sized,
pub fn poll_next(&mut self, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> where
Self: Unpin, [src][−]
Self: Unpin,
A convenience for calling Stream::poll_next() on !Unpin types.
pub fn next(&mut self) -> NextFuture<'_, Self>ⓘNotable traits for NextFuture<'_, S>
impl<'_, S> Future for NextFuture<'_, S> where
S: Stream + Unpin + ?Sized, type Output = Option<<S as Stream>::Item>; where
Self: Unpin, [src][−]
Notable traits for NextFuture<'_, S>
impl<'_, S> Future for NextFuture<'_, S> where
S: Stream + Unpin + ?Sized, type Output = Option<<S as Stream>::Item>;Self: Unpin,
Retrieves the next item in the stream. Read more
pub fn try_next<T, E>(&mut self) -> TryNextFuture<'_, Self>ⓘNotable traits for TryNextFuture<'_, S>
impl<'_, T, E, S> Future for TryNextFuture<'_, S> where
S: Stream<Item = Result<T, E>> + Unpin + ?Sized, type Output = Result<Option<T>, E>; where
Self: Stream<Item = Result<T, E>> + Unpin, [src][−]
Notable traits for TryNextFuture<'_, S>
impl<'_, T, E, S> Future for TryNextFuture<'_, S> where
S: Stream<Item = Result<T, E>> + Unpin + ?Sized, type Output = Result<Option<T>, E>;Self: Stream<Item = Result<T, E>> + Unpin,
Retrieves the next item in the stream. Read more
pub fn count(self) -> CountFuture<Self>ⓘNotable traits for CountFuture<S>
impl<S> Future for CountFuture<S> where
S: Stream + ?Sized, type Output = usize;[src][−]
Notable traits for CountFuture<S>
impl<S> Future for CountFuture<S> where
S: Stream + ?Sized, type Output = usize;Counts the number of items in the stream. Read more
pub fn map<T, F>(self, f: F) -> Map<Self, F> where
F: FnMut(Self::Item) -> T, [src][−]
F: FnMut(Self::Item) -> T,
Maps items of the stream to new values using a closure. Read more
pub fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where
F: FnMut(Self::Item) -> U,
U: Stream, [src][−]
F: FnMut(Self::Item) -> U,
U: Stream,
Maps items to streams and then concatenates them. Read more
pub fn flatten(self) -> Flatten<Self> where
Self::Item: Stream, [src][−]
Self::Item: Stream,
Concatenates inner streams. Read more
pub fn then<F, Fut>(self, f: F) -> Then<Self, F, Fut> where
F: FnMut(Self::Item) -> Fut,
Fut: Future, [src][−]
F: FnMut(Self::Item) -> Fut,
Fut: Future,
Maps items of the stream to new values using an async closure. Read more
pub fn filter<P>(self, predicate: P) -> Filter<Self, P> where
P: FnMut(&Self::Item) -> bool, [src][−]
P: FnMut(&Self::Item) -> bool,
Keeps items of the stream for which predicate returns true. Read more
pub fn filter_map<T, F>(self, f: F) -> FilterMap<Self, F> where
F: FnMut(Self::Item) -> Option<T>, [src][−]
F: FnMut(Self::Item) -> Option<T>,
Filters and maps items of the stream using a closure. Read more
pub fn take(self, n: usize) -> Take<Self>[src][−]
Takes only the first n items of the stream. Read more
pub fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where
P: FnMut(&Self::Item) -> bool, [src][−]
P: FnMut(&Self::Item) -> bool,
Takes items while predicate returns true. Read more
pub fn skip(self, n: usize) -> Skip<Self>[src][−]
Skips the first n items of the stream. Read more
pub fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
P: FnMut(&Self::Item) -> bool, [src][−]
P: FnMut(&Self::Item) -> bool,
Skips items while predicate returns true. Read more
pub fn step_by(self, step: usize) -> StepBy<Self>[src][−]
Yields every stepth item. Read more
pub fn chain<U>(self, other: U) -> Chain<Self, U> where
U: Stream<Item = Self::Item>, [src][−]
U: Stream<Item = Self::Item>,
Appends another stream to the end of this one. Read more
pub fn cloned<'a, T>(self) -> Cloned<Self> where
Self: Stream<Item = &'a T>,
T: Clone + 'a, [src][−]
Self: Stream<Item = &'a T>,
T: Clone + 'a,
Clones all items. Read more
pub fn copied<'a, T>(self) -> Copied<Self> where
Self: Stream<Item = &'a T>,
T: Copy + 'a, [src][−]
Self: Stream<Item = &'a T>,
T: Copy + 'a,
Copies all items. Read more
pub fn collect<C>(self) -> CollectFuture<Self, C>ⓘNotable traits for CollectFuture<S, C>
impl<S, C> Future for CollectFuture<S, C> where
C: Default + Extend<<S as Stream>::Item>,
S: Stream, type Output = C; where
C: Default + Extend<Self::Item>, [src][−]
Notable traits for CollectFuture<S, C>
impl<S, C> Future for CollectFuture<S, C> where
C: Default + Extend<<S as Stream>::Item>,
S: Stream, type Output = C;C: Default + Extend<Self::Item>,
Collects all items in the stream into a collection. Read more
pub fn try_collect<T, E, C>(self) -> TryCollectFuture<Self, C>ⓘNotable traits for TryCollectFuture<S, C>
impl<T, E, S, C> Future for TryCollectFuture<S, C> where
C: Default + Extend<T>,
S: Stream<Item = Result<T, E>>, type Output = Result<C, E>; where
Self: Stream<Item = Result<T, E>>,
C: Default + Extend<T>, [src][−]
Notable traits for TryCollectFuture<S, C>
impl<T, E, S, C> Future for TryCollectFuture<S, C> where
C: Default + Extend<T>,
S: Stream<Item = Result<T, E>>, type Output = Result<C, E>;Self: Stream<Item = Result<T, E>>,
C: Default + Extend<T>,
Collects all items in the fallible stream into a collection. Read more
pub fn partition<B, P>(self, predicate: P) -> PartitionFuture<Self, P, B>ⓘ where
P: FnMut(&Self::Item) -> bool,
B: Default + Extend<Self::Item>, [src][−]
P: FnMut(&Self::Item) -> bool,
B: Default + Extend<Self::Item>,
Partitions items into those for which predicate is true and those for which it is
false, and then collects them into two collections. Read more
pub fn fold<T, F>(self, init: T, f: F) -> FoldFuture<Self, F, T>ⓘNotable traits for FoldFuture<S, F, T>
impl<S, F, T> Future for FoldFuture<S, F, T> where
F: FnMut(T, <S as Stream>::Item) -> T,
S: Stream, type Output = T; where
F: FnMut(T, Self::Item) -> T, [src][−]
Notable traits for FoldFuture<S, F, T>
impl<S, F, T> Future for FoldFuture<S, F, T> where
F: FnMut(T, <S as Stream>::Item) -> T,
S: Stream, type Output = T;F: FnMut(T, Self::Item) -> T,
Accumulates a computation over the stream. Read more
pub fn try_fold<T, E, F, B>(
&mut self,
init: B,
f: F
) -> TryFoldFuture<'_, Self, F, B>ⓘNotable traits for TryFoldFuture<'a, S, F, B>
impl<'a, T, E, S, F, B> Future for TryFoldFuture<'a, S, F, B> where
F: FnMut(B, T) -> Result<B, E>,
S: Stream<Item = Result<T, E>> + Unpin, type Output = Result<B, E>; where
Self: Stream<Item = Result<T, E>> + Unpin,
F: FnMut(B, T) -> Result<B, E>, [src][−]
&mut self,
init: B,
f: F
) -> TryFoldFuture<'_, Self, F, B>ⓘ
Notable traits for TryFoldFuture<'a, S, F, B>
impl<'a, T, E, S, F, B> Future for TryFoldFuture<'a, S, F, B> where
F: FnMut(B, T) -> Result<B, E>,
S: Stream<Item = Result<T, E>> + Unpin, type Output = Result<B, E>;Self: Stream<Item = Result<T, E>> + Unpin,
F: FnMut(B, T) -> Result<B, E>,
Accumulates a fallible computation over the stream. Read more
pub fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where
F: FnMut(&mut St, Self::Item) -> Option<B>, [src][−]
F: FnMut(&mut St, Self::Item) -> Option<B>,
Maps items of the stream to new values using a state value and a closure. Read more
pub fn fuse(self) -> Fuse<Self>[src][−]
pub fn cycle(self) -> Cycle<Self> where
Self: Clone, [src][−]
Self: Clone,
Repeats the stream from beginning to end, forever. Read more
pub fn enumerate(self) -> Enumerate<Self>[src][−]
Enumerates items, mapping them to (index, item). Read more
pub fn inspect<F>(self, f: F) -> Inspect<Self, F> where
F: FnMut(&Self::Item), [src][−]
F: FnMut(&Self::Item),
Calls a closure on each item and passes it on. Read more
pub fn nth(&mut self, n: usize) -> NthFuture<'_, Self>ⓘ where
Self: Unpin, [src][−]
Self: Unpin,
Gets the nth item of the stream. Read more
pub fn last(self) -> LastFuture<Self>ⓘNotable traits for LastFuture<S>
impl<S> Future for LastFuture<S> where
S: Stream, type Output = Option<<S as Stream>::Item>;[src][−]
Notable traits for LastFuture<S>
impl<S> Future for LastFuture<S> where
S: Stream, type Output = Option<<S as Stream>::Item>;Returns the last item in the stream. Read more
pub fn find<P>(&mut self, predicate: P) -> FindFuture<'_, Self, P>ⓘ where
Self: Unpin,
P: FnMut(&Self::Item) -> bool, [src][−]
Self: Unpin,
P: FnMut(&Self::Item) -> bool,
Finds the first item of the stream for which predicate returns true. Read more
pub fn find_map<F, B>(&mut self, f: F) -> FindMapFuture<'_, Self, F>ⓘ where
Self: Unpin,
F: FnMut(Self::Item) -> Option<B>, [src][−]
Self: Unpin,
F: FnMut(Self::Item) -> Option<B>,
pub fn position<P>(&mut self, predicate: P) -> PositionFuture<'_, Self, P>ⓘ where
Self: Unpin,
P: FnMut(Self::Item) -> bool, [src][−]
Self: Unpin,
P: FnMut(Self::Item) -> bool,
Finds the index of the first item of the stream for which predicate returns true. Read more
pub fn all<P>(&mut self, predicate: P) -> AllFuture<'_, Self, P>ⓘ where
Self: Unpin,
P: FnMut(Self::Item) -> bool, [src][−]
Self: Unpin,
P: FnMut(Self::Item) -> bool,
Tests if predicate returns true for all items in the stream. Read more
pub fn any<P>(&mut self, predicate: P) -> AnyFuture<'_, Self, P>ⓘ where
Self: Unpin,
P: FnMut(Self::Item) -> bool, [src][−]
Self: Unpin,
P: FnMut(Self::Item) -> bool,
Tests if predicate returns true for any item in the stream. Read more
pub fn for_each<F>(self, f: F) -> ForEachFuture<Self, F>ⓘNotable traits for ForEachFuture<S, F>
impl<S, F> Future for ForEachFuture<S, F> where
F: FnMut(<S as Stream>::Item),
S: Stream, type Output = (); where
F: FnMut(Self::Item), [src][−]
Notable traits for ForEachFuture<S, F>
impl<S, F> Future for ForEachFuture<S, F> where
F: FnMut(<S as Stream>::Item),
S: Stream, type Output = ();F: FnMut(Self::Item),
Calls a closure on each item of the stream. Read more
pub fn try_for_each<F, E>(&mut self, f: F) -> TryForEachFuture<'_, Self, F>ⓘ where
Self: Unpin,
F: FnMut(Self::Item) -> Result<(), E>, [src][−]
Self: Unpin,
F: FnMut(Self::Item) -> Result<(), E>,
Calls a fallible closure on each item of the stream, stopping on first error. Read more
pub fn zip<U>(self, other: U) -> Zip<Self, U> where
U: Stream, [src][−]
U: Stream,
Zips up two streams into a single stream of pairs. Read more
pub fn unzip<A, B, FromA, FromB>(self) -> UnzipFuture<Self, FromA, FromB>ⓘ where
Self: Stream<Item = (A, B)>,
FromA: Default + Extend<A>,
FromB: Default + Extend<B>, [src][−]
Self: Stream<Item = (A, B)>,
FromA: Default + Extend<A>,
FromB: Default + Extend<B>,
Collects a stream of pairs into a pair of collections. Read more
pub fn or<S>(self, other: S) -> Or<Self, S> where
S: Stream<Item = Self::Item>, [src][−]
S: Stream<Item = Self::Item>,
Merges with other stream, preferring items from self whenever both streams are ready. Read more
pub fn race<S>(self, other: S) -> Race<Self, S> where
S: Stream<Item = Self::Item>, [src][−]
S: Stream<Item = Self::Item>,
Merges with other stream, with no preference for either stream when both are ready. Read more
pub fn boxed<'a>(
self
) -> Pin<Box<dyn Stream<Item = Self::Item> + 'a + Send, Global>>ⓘ where
Self: Send + 'a, [src][−]
self
) -> Pin<Box<dyn Stream<Item = Self::Item> + 'a + Send, Global>>ⓘ where
Self: Send + 'a,
Boxes the stream and changes its type to dyn Stream + Send + 'a. Read more
pub fn boxed_local<'a>(
self
) -> Pin<Box<dyn Stream<Item = Self::Item> + 'a, Global>>ⓘ where
Self: 'a, [src][−]
self
) -> Pin<Box<dyn Stream<Item = Self::Item> + 'a, Global>>ⓘ where
Self: 'a,
Boxes the stream and changes its type to dyn Stream + 'a. Read more
impl<T, U> TryFrom<U> for T where
U: Into<T>, [src][+]
U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src][−]
Performs the conversion.
impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src][+]
U: TryFrom<T>,
type Error = <U as TryFrom<T>>::Error
The type returned in the event of a conversion error.
pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>[src][−]
Performs the conversion.
impl<S, T, E> TryStream for S where
S: Stream<Item = Result<T, E>> + ?Sized, [src][+]
S: Stream<Item = Result<T, E>> + ?Sized,
type Ok = T
The type of successful values yielded by this future
type Error = E
The type of failures yielded by this future
pub fn try_poll_next(
self: Pin<&mut S>,
cx: &mut Context<'_>
) -> Poll<Option<Result<<S as TryStream>::Ok, <S as TryStream>::Error>>>[src][−]
self: Pin<&mut S>,
cx: &mut Context<'_>
) -> Poll<Option<Result<<S as TryStream>::Ok, <S as TryStream>::Error>>>
Poll this TryStream as if it were a Stream. Read more