I'm not sure if you're aware of it, but your code modifies @a since $_ in map and for aliases the current list element. If you don't want this, you'd have to localize $_ or to copy the current element to a new lexical variable.

In reply to Re: Basic list manipulation, and a bit of map() confusion... by Prof Vince
in thread Basic list manipulation, and a bit of map() confusion... by cmv

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