`scan` template args reodered to the same order as `Iterator::scan`
@@ -566,7 +566,7 @@ pub trait StreamExt: Stream {
/// assert_eq!(vec![1, 2, 3], stream.collect::<Vec<_>>().await);
/// # });
/// ```
- fn scan<B, Fut, S, F>(self, initial_state: S, f: F) -> Scan<Self, S, Fut, F>
+ fn scan<S, B, Fut, F>(self, initial_state: S, f: F) -> Scan<Self, S, Fut, F>
where
F: FnMut(&mut S, Self::Item) -> Fut,
Fut: Future<Output = Option<B>>,
