That's a very interesting thread - thank you. I kinda got most of this, although not so clearly. The problem is that not all my co-workers get this, so I sometimes spend time dealing with the ramifications of their code :-) And this was somewhat of the problem here. (The problem was that the writer of the code in question didn't know the ramifications ... and that was me, because it was the first piece of perl code I had ever, ever written - 3+ years old, and in bad need of replacing. My co-workers still don't know the ramifications, however we now have coding standards that bypass the ramifications: while(<FH>) isn't allowed, and $_ should be avoided where it can. map, grep, etc., cannot avoid it, so go ahead there.)