Struct futures::stream::Then

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

A stream combinator which chains a computation onto each item produced by a stream.

This structure is produced by the Stream::then method.

Trait Implementations

impl<S, U, F> Sink for Then<S, U, F> where
    S: Sink,
    U: IntoFuture, 

type SinkItem = <S as Sink>::SinkItem

The type of value that the sink accepts.

type SinkError = <S as Sink>::SinkError

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

fn poll_ready(
    &mut self,
    cx: &mut Context
) -> Result<Async<()>, <Then<S, U, F> as Sink>::SinkError>

Attempts to prepare the Sink to receive a value.

fn start_send(
    &mut self,
    item: <Then<S, U, F> as Sink>::SinkItem
) -> Result<(), <Then<S, U, F> as Sink>::SinkError>

Begin the process of sending a value to the sink. Each call to this function must be proceeded by a successful call to poll_ready which returned Ok(Async::Ready(())).

fn poll_flush(
    &mut self,
    cx: &mut Context
) -> Result<Async<()>, <Then<S, U, F> as Sink>::SinkError>

Flush any remaining output from this sink.

fn poll_close(
    &mut self,
    cx: &mut Context
) -> Result<Async<()>, <Then<S, U, F> as Sink>::SinkError>

Flush any remaining output and close this sink, if necessary.

impl<S, U, F> Stream for Then<S, U, F> where
    F: FnMut(Result<<S as Stream>::Item, <S as Stream>::Error>) -> U,
    S: Stream,
    U: IntoFuture, 

type Item = <U as IntoFuture>::Item

Values yielded by the stream.

type Error = <U as IntoFuture>::Error

Errors yielded by the stream.

fn poll_next(
    &mut self,
    cx: &mut Context
) -> Result<Async<Option<<U as IntoFuture>::Item>>, <U as IntoFuture>::Error>

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.

impl<S, U, F> Debug for Then<S, U, F> where
    F: Debug,
    S: Debug,
    U: Debug + IntoFuture,
    <U as IntoFuture>::Future: Debug, 

fn fmt(&self, __arg_0: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.