I didn’t know you could do that. I really like this syntax, but it works out nicer in Python where you don’t have to worry about passing references or values. A common case (for me) is passing in the first parameter by value (like an i32, for example). In this case, this syntax fails. So I can’t do simple things like let v2: Vec<i32> = v.iter().map(double).collect() (where double doubles an element) without modifying the double function itself. Really annoying.
