in reply to Perl6: too bad non-greediness is not made the default
in thread Parsing with Perl 6
The only thing I regret is that matching non greediness has not been made the default.
Non-greediness is only useful if you have something following the non-greediness. For example, /(\d*)/ would not be useful at all: it would always succeed, matching and capturing an empty string. /(\d+)/ would be equivalent to /(\d)/, because a non-greedy expression doesn't take more than the absolute minimum.
If you use non-greedy quantifiers now, think about the efficiency that is gained by re-writing for greediness. Suppose you have /"(.*?)"/ - it can be written as /"([^"]*)"/, which is much more efficient. With backtracking disabled, as jryan did in his example (with the new : meta character), it's even more efficient (in case the subject string is not well formed).
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Re: Re: Perl6: too bad non-greediness is not made the default
by stefp (Vicar) on Jul 06, 2002 at 15:46 UTC