funny that I just read that section of "Effective Perl" last night (while sitting on my toilet:-). To summarize: use grep to select, use map to transform, in either case, don't change $_. It's interesting to note that the OP is a combination of select and transform.

In reply to Re: modifying $_ in map (was Re: A perverse use of grep) by johnnywang
in thread A perverse use of grep by eyepopslikeamosquito

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