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use std::pin::Pin;
use std::future::Future;
use crate::task::{Context, Poll};
pub async fn poll_fn<F, T>(f: F) -> T
where
F: FnMut(&mut Context<'_>) -> Poll<T>,
{
let fut = PollFn { f };
fut.await
}
struct PollFn<F> {
f: F,
}
impl<F> Unpin for PollFn<F> {}
impl<T, F> Future for PollFn<F>
where
F: FnMut(&mut Context<'_>) -> Poll<T>,
{
type Output = T;
fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
(&mut self.f)(cx)
}
}