I gotta ask - where might be an explanation of the implicit int() within the subscripting []'s?   It's so beautiful and dreadful at the same time.

I've seen something like this done before, a long time ago, but I guess I just accepted it as 'magic'.   I was reminded on CB that a FP number wouldn't make any sense as a subscript and so the DWIMish gnomes happily fixed the value.   But sometimes I get this panicky feeling that if the magic isn't documented, it'll run away when I'm not looking.