Struct futures_util::sink::With

#[must_use = "sinks do nothing unless polled"]
pub struct With<Si, U, Fut, F> where
    Si: Sink,
    F: FnMut(U) -> Fut,
    Fut: Future,  { /* fields omitted */ }

Sink for the Sink::with combinator, chaining a computation to run prior to pushing a value into the underlying sink.

Methods

impl<Si, U, Fut, F, E> With<Si, U, Fut, F> where     Si: Sink,     F: FnMut(U) -> Fut,     Fut: Future<Output = Result<Si::SinkItem, E>>,     E: From<Si::SinkError>,

Important traits for &'a mut W

impl<'a, W> Write for &'a mut W where
    W: Write + ?Sized, impl<'a, R> Read for &'a mut R where
    R: Read + ?Sized, impl<'a, I> Iterator for &'a mut I where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

pub fn get_ref(&self) -> &Si

Get a shared reference to the inner sink.

Important traits for &'a mut W

impl<'a, W> Write for &'a mut W where
    W: Write + ?Sized, impl<'a, R> Read for &'a mut R where
    R: Read + ?Sized, impl<'a, I> Iterator for &'a mut I where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

pub fn get_mut(&mut self) -> &mut Si

Get a mutable reference to the inner sink.

pub fn into_inner(self) -> Si

Consumes this combinator, returning the underlying sink.

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<Si: Debug, U: Debug, Fut: Debug, F: Debug> Debug for With<Si, U, Fut, F> where     Si: Sink,     F: FnMut(U) -> Fut,     Fut: Future,     Si::SinkItem: Debug,

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<Si, U, Fut, F> Unpin for With<Si, U, Fut, F> where     Si: Sink + Unpin,     F: FnMut(U) -> Fut,     Fut: Future + Unpin,

impl<S, U, Fut, F> Stream for With<S, U, Fut, F> where     S: Stream + Sink,     F: FnMut(U) -> Fut,     Fut: Future,

type Item = S::Item

Values yielded by the stream.

fn poll_next(self: PinMut<Self>, cx: &mut Context) -> Poll<Option<S::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.

impl<Si, U, Fut, F, E> Sink for With<Si, U, Fut, F> where     Si: Sink,     F: FnMut(U) -> Fut,     Fut: Future<Output = Result<Si::SinkItem, E>>,     E: From<Si::SinkError>,

type SinkItem = U

The type of value that the sink accepts.

type SinkError = E

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

fn poll_ready(     self: PinMut<Self>,     cx: &mut Context ) -> Poll<Result<(), Self::SinkError>>

Attempts to prepare the Sink to receive a value.

fn start_send(     self: PinMut<Self>,     item: Self::SinkItem ) -> Result<(), Self::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(Poll::Ready(())).

fn poll_flush(     self: PinMut<Self>,     cx: &mut Context ) -> Poll<Result<(), Self::SinkError>>

Flush any remaining output from this sink.

fn poll_close(     self: PinMut<Self>,     cx: &mut Context ) -> Poll<Result<(), Self::SinkError>>

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