O Monks,

This article http://swtch.com/~rsc/regexp/regexp1.html critizes Perl's regexp engine and gives an example where it performs very badly. I'm trying to convert the example, given in pseudocode, into real perl code, and not succeeding. Can anyone help?

Here are the things I can't figure out:

(1) They use a repetition count n twice. This could mean either that (a) the two counts have to be the same, or that (b) they could be different. Which one would make sense here?

(2) In case (a), I don't know how to code the constraint on the counts into a perl regexp. In case (b), I get this perl -e 'if (("a" x 29)=~/(a?)*a*/) {print 1}', which doesn't have the poor performance they claim.

In reply to regexp puzzle by bcrowell2

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