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use sdt::pin::Pin;
use std::future::Future;
use std::marker;
use std::task::{Context, Poll};
/// Future for the [`pending()`] function.
#[derive(Debug)]
#[must_use = "futures do nothing unless you `.await` or poll them"]
struct Pending<T> {
_data: marker::PhantomData<T>,
}
/// Creates a future which never resolves, representing a computation that never
/// finishes.
///
/// The returned future will forever return [`Poll::Pending`].
///
/// # Examples
///
/// ```no_run
/// use tokio::future;
///
/// #[tokio::main]
/// async fn main {
/// future::pending().await;
/// unreachable!();
/// }
/// ```
pub async fn pending() -> ! {
Pending {
_data: marker::PhantomData,
}
.await
}
impl<T> Future for Pending<T> {
type Output = !;
fn poll(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<T> {
Poll::Pending
}
}
impl<T> Unpin for Pending<T> {}
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