blob: cccad399e5bacc62a5eb5f219095699190a708dc [file] [log] [blame]
use sink::Sink;
use {Poll, StartSend, Stream};
/// Sink for the `Sink::sink_map_err` combinator.
#[derive(Debug)]
#[must_use = "sinks do nothing unless polled"]
pub struct SinkMapErr<S, F> {
sink: S,
f: Option<F>,
}
pub fn new<S, F>(s: S, f: F) -> SinkMapErr<S, F> {
SinkMapErr { sink: s, f: Some(f) }
}
impl<S, E> SinkMapErr<S, E> {
/// Get a shared reference to the inner sink.
pub fn get_ref(&self) -> &S {
&self.sink
}
/// Get a mutable reference to the inner sink.
pub fn get_mut(&mut self) -> &mut S {
&mut self.sink
}
/// 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.
pub fn into_inner(self) -> S {
self.sink
}
}
impl<S, F, E> Sink for SinkMapErr<S, F>
where S: Sink,
F: FnOnce(S::SinkError) -> E,
{
type SinkItem = S::SinkItem;
type SinkError = E;
fn start_send(&mut self, item: Self::SinkItem) -> StartSend<Self::SinkItem, Self::SinkError> {
self.sink.start_send(item).map_err(|e| self.f.take().expect("cannot use MapErr after an error")(e))
}
fn poll_complete(&mut self) -> Poll<(), Self::SinkError> {
self.sink.poll_complete().map_err(|e| self.f.take().expect("cannot use MapErr after an error")(e))
}
fn close(&mut self) -> Poll<(), Self::SinkError> {
self.sink.close().map_err(|e| self.f.take().expect("cannot use MapErr after an error")(e))
}
}
impl<S: Stream, F> Stream for SinkMapErr<S, F> {
type Item = S::Item;
type Error = S::Error;
fn poll(&mut self) -> Poll<Option<S::Item>, S::Error> {
self.sink.poll()
}
}