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use core::marker;
use futures_core::{Future, Poll, Async};
use futures_core::task;
#[derive(Debug)]
#[must_use = "futures do nothing unless polled"]
pub struct Empty<T, E> {
_data: marker::PhantomData<(T, E)>,
}
pub fn empty<T, E>() -> Empty<T, E> {
Empty { _data: marker::PhantomData }
}
impl<T, E> Future for Empty<T, E> {
type Item = T;
type Error = E;
fn poll(&mut self, _: &mut task::Context) -> Poll<T, E> {
Ok(Async::Pending)
}
}