Yes, you're looking at the right graph. If you look at the left hand side, that's running a match on a single-byte string, so essentially all the time is in construction. Of course, I suppose that it's using a fairly small (a?a) regex, so it's not as illustrative as I had hoped.

What I said before is still true -- you're only parsing the regex, which is all that you do for a backtracking implementation too.

I'd be perfectly happy to rerelease the code under an appropriate license, but I doubt you'd want it -- it's nowhere near parsing Perl's regexes. It doesn't even parse full egrep regexes. It's really only meant to be a proof of concept.

In reply to Re^5: Perl regexp matching is slow?? by rsc
in thread Perl regexp matching is slow?? by smahesh

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