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use core::marker;
use core::pin::Pin;
use futures_core::future::Future;
use futures_core::task::{LocalWaker, Poll};
#[derive(Debug)]
#[must_use = "futures do nothing unless polled"]
pub struct Empty<T> {
_data: marker::PhantomData<T>,
}
pub fn empty<T>() -> Empty<T> {
Empty { _data: marker::PhantomData }
}
impl<T> Future for Empty<T> {
type Output = T;
fn poll(self: Pin<&mut Self>, _: &LocalWaker) -> Poll<T> {
Poll::Pending
}
}