My point was that you can replace whole script with this one-liner.

If you will embed it into some bigger script than it will do cause new perl interpreter to spawn. As for Really Bad side effects: it will be perfomance hit (but you should not care about it in this case) and probably it is not very good style. At least I would not embed such one-liner in my Perl code myself because IMHO embedding Perl code inside Perl code looks somewhat ugly.

Probably foreach loop could be written slightly shorter but in general your original script is ok. I just wanted to show fast dirty way to do the same.