Had you run with warnings on (perl -w), perl would have given you a better clue about its interpretation. You would have seen that perl thinks $bef[$mid] is an element of an array.

Knowing that, I think your results will now make perfect sense to you. Since $bef[$mid] is not defined, $bef[$mid]$aft becomes a string containing undef followed by 'after.' $bef$mid[$aft] becomes 'before' followed undef.

Escape the square brackets with a backslash, and all will be well.

I think this was mainly just an oversight. One of those things that, until it's pointed out to you, you can't see it at all, but once you see it, it's obvious. :-)

Russ

In reply to RE: Regexp: not what I'd expected by Russ
in thread Regexp: not what I'd expected by greenhorn

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