blob: c53fb8023863dfd8d902ef60aa4dde9c9f4f88e7 (
plain)
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
|
use core::marker;
use stream::Stream;
use {Poll, Async};
/// A stream which contains no elements.
///
/// This stream can be created with the `stream::empty` function.
#[derive(Debug)]
#[must_use = "streams do nothing unless polled"]
pub struct Empty<T, E> {
_data: marker::PhantomData<(T, E)>,
}
/// Creates a stream which contains no elements.
///
/// The returned stream will always return `Ready(None)` when polled.
pub fn empty<T, E>() -> Empty<T, E> {
Empty { _data: marker::PhantomData }
}
impl<T, E> Stream for Empty<T, E> {
type Item = T;
type Error = E;
fn poll(&mut self) -> Poll<Option<Self::Item>, Self::Error> {
Ok(Async::Ready(None))
}
}
|
