# skip.rs - source
Source of the Rust file `/home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/futures-util-0.3.13/src/stream/stream/skip.rs`.
Keywords: rust, rustlang, rust-lang

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    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 as usize);
            let upper = match upper {
                Some(x) => Some(x.saturating_sub(self.remaining as usize)),
                None => None,
            };

            (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);
    }