In my opinion, one of the worst things you can do with respect to subroutines is allow them to accept values through broader-scope "osmosis". My opinion is that all subroutine variables should be lexically scoped to the boundries of the subroutine.
Huh?!? That's exactly what a closure does. And closures are useful!

Update: I hadn't noticed you mention closures yourself. I apologize. But in any case some caution is required IMHO before stating such a claim as the above. I.e. I wouldn't talk about "one of the worst things you can do...", but of "you must pay a lot of attention when you...", instead.

In reply to Re^2: Ghostly subroutine variables haunting me in subsequent calls by blazar
in thread Ghostly subroutine variables haunting me in subsequent calls by moonunit

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