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in reply to Re: Perl regexp matching is slow??
in thread Perl regexp matching is slow??

Second, you must understand that Perl set the bar for regexes when P5 was released over 10 years ago. […] In that time, a lot of theoretical work has been done.

You missed the part where the author writes he will be reviewing “a regular expression search algorithm invented by Ken Thompson in the mid-1960s.”

Makeshifts last the longest.

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Re^3: Perl regexp matching is slow??
by dragonchild (Archbishop) on Feb 07, 2007 at 14:46 UTC
    No, I didn't miss that. New code is always being written to implement old algorithms. Just because an algorithm exists doesn't mean that there is an efficient implementation of it. Theoretical work has advanced in the implementation of these algorithms and in how the various algorithms can be used to solve the problems Perl's regexes need to solve.

    My criteria for good software:
    1. Does it work?
    2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?
      I guess you missed the part where it was used to write UNIX's lex(1) and grep(1), too.