1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
use core::marker;
use {Future, Poll, Async};
#[must_use = "futures do nothing unless polled"]
pub struct Finished<T, E> {
t: Option<T>,
_e: marker::PhantomData<E>,
}
pub fn finished<T, E>(t: T) -> Finished<T, E> {
Finished { t: Some(t), _e: marker::PhantomData }
}
impl<T, E> Future for Finished<T, E> {
type Item = T;
type Error = E;
fn poll(&mut self) -> Poll<T, E> {
Ok(Async::Ready(self.t.take().expect("cannot poll Finished twice")))
}
}