Sha256: 61f7ec7fe25663d2c87cffaad19ed27eda032842edb8af731b521025b244f120
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Size: 1.69 KB
Versions: 25
Compression:
Stored size: 1.69 KB
Contents
use core::pin::Pin;
use futures_core::ready;
use futures_core::stream::{FusedStream, Stream};
use futures_core::task::{Context, Poll};
#[cfg(feature = "sink")]
use futures_sink::Sink;
use pin_project_lite::pin_project;
pin_project! {
/// Stream for the [`skip`](super::StreamExt::skip) method.
#[derive(Debug)]
#[must_use = "streams do nothing unless polled"]
pub struct Skip<St> {
#[pin]
stream: St,
remaining: usize,
}
}
impl<St: Stream> Skip<St> {
pub(super) fn new(stream: St, n: usize) -> Self {
Self { stream, remaining: n }
}
delegate_access_inner!(stream, St, ());
}
impl<St: FusedStream> FusedStream for Skip<St> {
fn is_terminated(&self) -> bool {
self.stream.is_terminated()
}
}
impl<St: Stream> Stream for Skip<St> {
type Item = St::Item;
fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<St::Item>> {
let mut this = self.project();
while *this.remaining > 0 {
if ready!(this.stream.as_mut().poll_next(cx)).is_some() {
*this.remaining -= 1;
} else {
return Poll::Ready(None);
}
}
this.stream.poll_next(cx)
}
fn size_hint(&self) -> (usize, Option<usize>) {
let (lower, upper) = self.stream.size_hint();
let lower = lower.saturating_sub(self.remaining);
let upper = upper.map(|x| x.saturating_sub(self.remaining));
(lower, upper)
}
}
// Forwarding impl of Sink from the underlying stream
#[cfg(feature = "sink")]
impl<S, Item> Sink<Item> for Skip<S>
where
S: Stream + Sink<Item>,
{
type Error = S::Error;
delegate_sink!(stream, Item);
}
Version data entries
25 entries across 25 versions & 1 rubygems