So in other words, a regular expression is more specific than another, if it "matches less" than that other rx.

Well, apart from the fact that this question isn't even well formulated (for instance, all the given regexes, except the first one, match an countable, infinite set of strings - and you cannot order such sets on size), I doubt the question is even computable. I don't think even if the simpler question "given two (Perl) regexes, determine whether they match the same set of strings" is computable.

Oh - yes and the computation of the "genericity/specifity" should be fast.
Hahahahaha. It's a little early for April 1.

In reply to Re: Analysis of Regular Expressions by JavaFan
in thread Analysis of Regular Expressions by PetaMem

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