blob: e3cb5ff49c66ad54ce0eed057412715d566830cb [file] [log] [blame]
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())))
}
}