1 use crate::lib::future::Future;
2 use crate::lib::marker::Unpin;
3 use crate::lib::pin::Pin;
4 use crate::lib::task::{Context, Poll};
5
6 // Replace usage of this with std::future::poll_fn once it stabilizes
7 pub struct PollFn<F> {
8 f: F,
9 }
10
11 impl<F> Unpin for PollFn<F> {}
12
poll_fn<T, F>(f: F) -> PollFn<F> where F: FnMut(&mut Context<'_>) -> Poll<T>,13 pub fn poll_fn<T, F>(f: F) -> PollFn<F>
14 where
15 F: FnMut(&mut Context<'_>) -> Poll<T>,
16 {
17 PollFn { f }
18 }
19
20 impl<T, F> Future for PollFn<F>
21 where
22 F: FnMut(&mut Context<'_>) -> Poll<T>,
23 {
24 type Output = T;
25
poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T>26 fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
27 (&mut self.f)(cx)
28 }
29 }
30