Struct futures::stream::Map

#[must_use = "streams do nothing unless polled"]
pub struct Map<S, F> { /* fields omitted */ }

[−] Expand description

A stream combinator which will change the type of a stream from one type to another.

This is produced by the Stream::map method.

Trait Implementations

impl<S, F, U> Stream for Map<S, F> where S: Stream, F: FnMut(S::Item) -> U

type Item = U

The type of item this stream will yield on success.

type Error = S::Error

The type of error this stream may generate.

fn poll(&mut self) -> Poll<Option<U>, S::Error>[−]

Attempt to pull out the next value of this stream, returning None if the stream is finished.

fn wait(self) -> Wait<Self> where Self: Sized[−]

Creates an iterator which blocks the current thread until each item of this stream is resolved.

fn boxed(self) -> BoxStream<Self::Item, Self::Error> where Self: Sized + Send + 'static[−]

Convenience function for turning this stream into a trait object.

fn into_future(self) -> StreamFuture<Self> where Self: Sized[−]

Converts this stream into a Future.

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

Converts a stream of type T to a stream of type U.

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

Converts a stream of error type T to a stream of error type U.

fn filter<F>(self, f: F) -> Filter<Self, F> where F: FnMut(&Self::Item) -> bool, Self: Sized[−]

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

fn filter_map<F, B>(self, f: F) -> FilterMap<Self, F> where F: FnMut(Self::Item) -> Option<B>, Self: Sized[−]

Filters the values produced by this stream while simultaneously mapping them to a different type.

fn then<F, U>(self, f: F) -> Then<Self, F, U> where F: FnMut(Result<Self::Item, Self::Error>) -> U, U: IntoFuture, Self: Sized[−]

Chain on a computation for when a value is ready, passing the resulting item to the provided closure f.

fn and_then<F, U>(self, f: F) -> AndThen<Self, F, U> where F: FnMut(Self::Item) -> U, U: IntoFuture<Error=Self::Error>, Self: Sized[−]

Chain on a computation for when a value is ready, passing the successful results to the provided closure f.

fn or_else<F, U>(self, f: F) -> OrElse<Self, F, U> where F: FnMut(Self::Error) -> U, U: IntoFuture<Item=Self::Item>, Self: Sized[−]

Chain on a computation for when an error happens, passing the erroneous result to the provided closure f.

fn collect(self) -> Collect<Self> where Self: Sized[−]

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

fn fold<F, T, Fut>(self, init: T, f: F) -> Fold<Self, F, Fut, T> where F: FnMut(T, Self::Item) -> Fut, Fut: IntoFuture<Item=T>, Self::Error: From<Fut::Error>, Self: Sized[−]

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

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

Flattens a stream of streams into just one continuous stream.

fn skip_while<P, R>(self, pred: P) -> SkipWhile<Self, P, R> where P: FnMut(&Self::Item) -> R, R: IntoFuture<Item=bool, Error=Self::Error>, Self: Sized[−]

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

fn for_each<F>(self, f: F) -> ForEach<Self, F> where F: FnMut(Self::Item) -> Result<(), Self::Error>, Self: Sized[−]

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

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

Creates a new stream of at most amt items of the underlying stream.

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

Creates a new stream which skips amt items of the underlying stream.

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

Fuse a stream such that poll will never again be called once it has finished.

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

Catches unwinding panics while polling the stream.

fn buffered(self, amt: usize) -> Buffered<Self> where Self::Item: IntoFuture<Error=Self::Error>, Self: Sized[−]

An adaptor for creating a buffered list of pending futures.

fn buffer_unordered(self, amt: usize) -> BufferUnordered<Self> where Self::Item: IntoFuture<Error=Self::Error>, Self: Sized[−]

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

fn merge<S>(self, other: S) -> Merge<Self, S> where S: Stream<Error=Self::Error>, Self: Sized[−]

An adapter for merging the output of two streams.

fn zip<S>(self, other: S) -> Zip<Self, S> where S: Stream<Error=Self::Error>, Self: Sized[−]

An adapter for zipping two streams together.

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

Creates a new stream which exposes a peek method.

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

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