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    use core::mem;
    use core::pin::Pin;
    use futures_core::future::{FusedFuture, Future};
    use futures_core::ready;
    use futures_core::stream::{FusedStream, TryStream};
    use futures_core::task::{Context, Poll};
    use pin_project_lite::pin_project;

    pin_project! {
        /// Future for the [`try_collect`](super::TryStreamExt::try_collect) method.
        #[derive(Debug)]
        #[must_use = "futures do nothing unless you `.await` or poll them"]
        pub struct TryCollect<St, C> {
            #[pin]
            stream: St,
            items: C,
        }
    }

    impl<St: TryStream, C: Default> TryCollect<St, C> {
        pub(super) fn new(s: St) -> Self {
            Self {
                stream: s,
                items: Default::default(),
            }
        }
    }

    impl<St, C> FusedFuture for TryCollect<St, C>
    where
        St: TryStream + FusedStream,
        C: Default + Extend<St::Ok>,
    {
        fn is_terminated(&self) -> bool {
            self.stream.is_terminated()
        }
    }

    impl<St, C> Future for TryCollect<St, C>
    where
        St: TryStream,
        C: Default + Extend<St::Ok>,
    {
        type Output = Result<C, St::Error>;

        fn poll(
            self: Pin<&mut Self>,
            cx: &mut Context<'_>,
        ) -> Poll<Self::Output> {
            let mut this = self.project();
            Poll::Ready(Ok(loop {
                match ready!(this.stream.as_mut().try_poll_next(cx)?) {
                    Some(x) => this.items.extend(Some(x)),
                    None => break mem::replace(this.items, Default::default()),
                }
            }))
        }
    }