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use core::marker::PhantomData;
use core::pin::Pin;
use futures_core::stream::Stream;
use futures_core::task::{Context, Poll};
#[derive(Debug)]
#[must_use = "streams do nothing unless polled"]
pub struct Empty<T> {
_phantom: PhantomData<T>
}
pub fn empty<T>() -> Empty<T> {
Empty {
_phantom: PhantomData
}
}
impl<T> Unpin for Empty<T> {}
impl<T> Stream for Empty<T> {
type Item = T;
fn poll_next(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Option<Self::Item>> {
Poll::Ready(None)
}
}