in reply to Perl6: too bad non-greediness is not made the default
in thread Parsing with Perl 6
I try to write my regexen backtracking-free, as, I believe, anyone should. And in that case greediness is very desired and useful most of the time. Non-greediness basically means that you match broader than you really need to - it works because you "forwardtrack", you gobble the string one submatch at a time. It is better to match more narrowly and greedily, since a greedy match will gobble up a lot of the string in one fell swoop and do less superfluous searching. In simple cases the regex optimizer is smart enough to simplify a non-greedy match into a Boyer-Moore search, but when you're working with a complex regex you really want to match narrowly and greedily.Regexen are a tricky art.
Makeshifts last the longest.
|Replies are listed 'Best First'.|
Re: Re: Perl6: too bad non-greediness is not made the default
by stefp (Vicar) on Jul 05, 2002 at 15:55 UTC
by Aristotle (Chancellor) on Jul 06, 2002 at 01:57 UTC