The docs for Vec::iter show the following type:

fn iter(&self) -> Iter<T>

As a result, I was puzzled that the following doesn't work:

let bar: Vec<&str> = vec!["a", "b", "c", "b"].iter().collect();

It turns out that that Iter implements an iterator with element type &T. On the Iter docs page we see type Item = &'a T but it's easy to overlook.

I think it would be worth adding a line to Vec::iter's documentation to say:

Iterator element type is &T.

This is the approach taken in itertools docs (example) and I think it helps significantly.