# Struct futures::stream::FilterMap [−] [src]

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

A combinator used to filter the results of a stream and simultaneously map them to a different type.

This structure is returned by the `Stream::filter_map` method.

## Methods

### `impl<S, F> FilterMap<S, F>`
[src]

#### `pub fn get_ref(&self) -> &S`
[src]

Acquires a reference to the underlying stream that this combinator is pulling from.

#### `pub fn get_mut(&mut self) -> &mut S`
[src]

Acquires a mutable reference to the underlying stream that this combinator is pulling from.

Note that care must be taken to avoid tampering with the state of the stream which may otherwise confuse this combinator.

#### `pub fn into_inner(self) -> S`
[src]

Consumes this combinator, returning the underlying stream.

Note that this may discard intermediate state of this combinator, so care should be taken to avoid losing resources when this is called.

## Trait Implementations

### `impl<S: Debug, F: Debug> Debug for FilterMap<S, F>`
[src]

#### `fn fmt(&self, __arg_0: &mut Formatter) -> Result`
[src]

Formats the value using the given formatter. Read more

### `impl<S, F> Sink for FilterMap<S, F> where
S: Sink,`
[src]

#### `type SinkItem = S::SinkItem`

The type of value that the sink accepts.

#### `type SinkError = S::SinkError`

The type of value produced by the sink when an error occurs.

#### `fn start_send(
&mut self,
item: S::SinkItem
) -> StartSend<S::SinkItem, S::SinkError>`
[src]

Begin the process of sending a value to the sink. Read more

#### `fn poll_complete(&mut self) -> Poll<(), S::SinkError>`
[src]

Flush all output from this sink, if necessary. Read more

#### `fn close(&mut self) -> Poll<(), S::SinkError>`
[src]

A method to indicate that no more values will ever be pushed into this sink. Read more

#### `fn wait(self) -> Wait<Self> where
Self: Sized,`
[src]

Creates a new object which will produce a synchronous sink. Read more

#### `fn with<U, F, Fut>(self, f: F) -> With<Self, U, F, Fut> where
F: FnMut(U) -> Fut,
Fut: IntoFuture<Item = Self::SinkItem>,
Fut::Error: From<Self::SinkError>,
Self: Sized,`
[src]

Composes a function in front of the sink. Read more

#### `fn with_flat_map<U, F, St>(self, f: F) -> WithFlatMap<Self, U, F, St> where
F: FnMut(U) -> St,
St: Stream<Item = Self::SinkItem, Error = Self::SinkError>,
Self: Sized,`
[src]

Composes a function in front of the sink. Read more

#### `fn sink_map_err<F, E>(self, f: F) -> SinkMapErr<Self, F> where
F: FnOnce(Self::SinkError) -> E,
Self: Sized,`
[src]

Transforms the error returned by the sink.

#### `fn sink_from_err<E: From<Self::SinkError>>(self) -> SinkFromErr<Self, E> where
Self: Sized,`
[src]

Map this sink's error to any error implementing `From` for this sink's `Error`, returning a new sink. Read more

#### `fn buffer(self, amt: usize) -> Buffer<Self> where
Self: Sized,`
[src]

Adds a fixed-size buffer to the current sink. Read more

#### `fn fanout<S>(self, other: S) -> Fanout<Self, S> where
Self: Sized,
Self::SinkItem: Clone,
S: Sink<SinkItem = Self::SinkItem, SinkError = Self::SinkError>,`
[src]

Fanout items to multiple sinks. Read more

#### `fn flush(self) -> Flush<Self> where
Self: Sized,`
[src]

A future that completes when the sink has finished processing all pending requests. Read more

#### `fn send(self, item: Self::SinkItem) -> Send<Self> where
Self: Sized,`
[src]

A future that completes after the given item has been fully processed into the sink, including flushing. Read more

#### `fn send_all<S>(self, stream: S) -> SendAll<Self, S> where
S: Stream<Item = Self::SinkItem>,
Self::SinkError: From<S::Error>,
Self: Sized,`
[src]

A future that completes after the given stream has been fully processed into the sink, including flushing. Read more

### `impl<S, F, B> Stream for FilterMap<S, F> where
S: Stream,
F: FnMut(S::Item) -> Option<B>,`
[src]

#### `type Item = B`

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<B>, S::Error>`
[src]

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

####
ⓘImportant traits for Wait<S>

### Important traits for Wait<S>

`impl<S: Stream> Iterator for Wait<S> type Item = Result<S::Item, S::Error>;`
`fn wait(self) -> Wait<Self> where
Self: Sized,`
[src]

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

#### `fn into_future(self) -> StreamFuture<Self> where
Self: Sized,`
[src]

Converts this stream into a `Future`. Read more

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

Converts a stream of type `T` to a stream of type `U`. Read more

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

Converts a stream of error type `T` to a stream of error type `U`. Read more

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

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

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

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

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

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

#### `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,`
[src]

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

#### `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,`
[src]

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

#### `fn collect(self) -> Collect<Self> 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

#### `fn concat2(self) -> Concat2<Self> where
Self: Sized,
Self::Item: Extend<<Self::Item as IntoIterator>::Item> + IntoIterator + Default,`
[src]

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

#### `fn concat(self) -> Concat<Self> where
Self: Sized,
Self::Item: Extend<<Self::Item as IntoIterator>::Item> + IntoIterator,`
[src]

Deprecated since 0.1.14

: please use `Stream::concat2` instead

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

#### `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,`
[src]

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

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

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

#### `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,`
[src]

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

#### `fn take_while<P, R>(self, pred: P) -> TakeWhile<Self, P, R> where
P: FnMut(&Self::Item) -> R,
R: IntoFuture<Item = bool, Error = Self::Error>,
Self: Sized,`
[src]

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

#### `fn for_each<F, U>(self, f: F) -> ForEach<Self, F, U> where
F: FnMut(Self::Item) -> U,
U: IntoFuture<Item = (), Error = Self::Error>,
Self: Sized,`
[src]

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

#### `fn from_err<E: From<Self::Error>>(self) -> FromErr<Self, E> where
Self: Sized,`
[src]

Map this stream's error to any error implementing `From` for this stream's `Error`, returning a new stream. Read more

#### `fn take(self, amt: u64) -> Take<Self> where
Self: Sized,`
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Creates a new stream of at most `amt` items of the underlying stream. Read more

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

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

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

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

#### `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,`
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Catches unwinding panics while polling the stream. Read more

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

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

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

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

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

Deprecated

: functionality provided by `select` now

An adapter for merging the output of two streams. Read more

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

An adapter for zipping two streams together. Read more

#### `fn chain<S>(self, other: S) -> Chain<Self, S> where
S: Stream<Item = Self::Item, Error = Self::Error>,
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<S>(self, other: S) -> Select<Self, S> where
S: Stream<Item = Self::Item, Error = Self::Error>,
Self: Sized,`
[src]

Creates a stream that selects the next element from either this stream or the provided one, whichever is ready first. Read more

#### `fn forward<S>(self, sink: S) -> Forward<Self, S> where
S: Sink<SinkItem = Self::Item>,
Self::Error: From<S::SinkError>,
Self: Sized,`
[src]

A future that completes after the given stream has been fully processed into the sink, including flushing. Read more

#### `fn split(self) -> (SplitSink<Self>, SplitStream<Self>) where
Self: Sink + Sized,`
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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

#### `fn inspect_err<F>(self, f: F) -> InspectErr<Self, F> where
F: FnMut(&Self::Error),
Self: Sized,`
[src]

Do something with the error of this stream, afterwards passing it on. Read more

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