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    use core::marker;

    use stream::Stream;
    use {Poll, Async};

    /// A stream which contains no elements.
    ///
    /// This stream can be created with the `stream::empty` function.
    #[derive(Debug)]
    #[must_use = "streams do nothing unless polled"]
    pub struct Empty<T, E> {
        _data: marker::PhantomData<(T, E)>,
    }

    /// Creates a stream which contains no elements.
    ///
    /// The returned stream will always return `Ready(None)` when polled.
    pub fn empty<T, E>() -> Empty<T, E> {
        Empty { _data: marker::PhantomData }
    }

    impl<T, E> Stream for Empty<T, E> {
        type Item = T;
        type Error = E;

        fn poll(&mut self) -> Poll<Option<Self::Item>, Self::Error> {
            Ok(Async::Ready(None))
        }
    }

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