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use crate::fmt::{self, Debug};
use crate::future::Future;
use crate::marker;
use crate::pin::Pin;
use crate::task::{Context, Poll};
#[stable(feature = "future_readiness_fns", since = "1.48.0")]
#[must_use = "futures do nothing unless you `.await` or poll them"]
pub struct Pending<T> {
_data: marker::PhantomData<fn() -> T>,
}
#[stable(feature = "future_readiness_fns", since = "1.48.0")]
pub fn pending<T>() -> Pending<T> {
Pending { _data: marker::PhantomData }
}
#[stable(feature = "future_readiness_fns", since = "1.48.0")]
impl<T> Future for Pending<T> {
type Output = T;
fn poll(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<T> {
Poll::Pending
}
}
#[stable(feature = "future_readiness_fns", since = "1.48.0")]
impl<T> Debug for Pending<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("Pending").finish()
}
}
#[stable(feature = "future_readiness_fns", since = "1.48.0")]
impl<T> Clone for Pending<T> {
fn clone(&self) -> Self {
pending()
}
}