diff options
Diffstat (limited to 'third_party/rust/futures-0.1.31/src/stream/repeat.rs')
-rw-r--r-- | third_party/rust/futures-0.1.31/src/stream/repeat.rs | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/third_party/rust/futures-0.1.31/src/stream/repeat.rs b/third_party/rust/futures-0.1.31/src/stream/repeat.rs new file mode 100644 index 0000000000..e3cb5ff49c --- /dev/null +++ b/third_party/rust/futures-0.1.31/src/stream/repeat.rs @@ -0,0 +1,53 @@ +use core::marker; + + +use stream::Stream; + +use {Async, Poll}; + + +/// Stream that produces the same element repeatedly. +/// +/// This structure is created by the `stream::repeat` function. +#[derive(Debug)] +#[must_use = "streams do nothing unless polled"] +pub struct Repeat<T, E> + where T: Clone +{ + item: T, + error: marker::PhantomData<E>, +} + +/// Create a stream which produces the same item repeatedly. +/// +/// Stream never produces an error or EOF. Note that you likely want to avoid +/// usage of `collect` or such on the returned stream as it will exhaust +/// available memory as it tries to just fill up all RAM. +/// +/// ```rust +/// use futures::*; +/// +/// let mut stream = stream::repeat::<_, bool>(10); +/// assert_eq!(Ok(Async::Ready(Some(10))), stream.poll()); +/// assert_eq!(Ok(Async::Ready(Some(10))), stream.poll()); +/// assert_eq!(Ok(Async::Ready(Some(10))), stream.poll()); +/// ``` +pub fn repeat<T, E>(item: T) -> Repeat<T, E> + where T: Clone +{ + Repeat { + item: item, + error: marker::PhantomData, + } +} + +impl<T, E> Stream for Repeat<T, E> + where T: Clone +{ + type Item = T; + type Error = E; + + fn poll(&mut self) -> Poll<Option<Self::Item>, Self::Error> { + Ok(Async::Ready(Some(self.item.clone()))) + } +} |