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use core::marker::Unpin;
use core::pin::Pin;
use futures_core::future::Future;
use futures_core::task::{LocalWaker, Poll};
use pin_utils::unsafe_pinned;
#[derive(Debug)]
#[must_use = "futures do nothing unless polled"]
pub struct UnitError<Fut> {
future: Fut,
}
impl<Fut> UnitError<Fut> {
unsafe_pinned!(future: Fut);
pub(super) fn new(future: Fut) -> UnitError<Fut> {
UnitError { future }
}
}
impl<Fut: Unpin> Unpin for UnitError<Fut> {}
impl<Fut, T> Future for UnitError<Fut>
where Fut: Future<Output = T>,
{
type Output = Result<T, ()>;
fn poll(mut self: Pin<&mut Self>, lw: &LocalWaker) -> Poll<Result<T, ()>> {
self.future().poll(lw).map(Ok)
}
}