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Re: Perl 5's "non-greedy" matching can be TOO greedy!

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From:
Deven T. Corzine
Date:
December 15, 2000 11:57
Subject:
Re: Perl 5's "non-greedy" matching can be TOO greedy!
Message ID:
Pine.LNX.4.10.10012151455120.31056-100000@escher.ties.org

On Fri, 15 Dec 2000, Deven T. Corzine wrote:

> Not at all.  I don't want it to keep looking after it finds the first
> match.  I want it to make sure that match isn't unnecessarily long, if
> non-greedy matching was in use.  Conceptually (I don't think this would be
> a good implementation), you find the first match as the current engine
> does, then search for the smallest possible match WITHIN that first match.
> Since it will already be as short as possible from the starting point, this
> amounts to advancing the starting point as far as possible without changing
> the ending point, as long as it still matches.

Actually, I'm not sure -- it's conceivable that the ending point would ALSO
move inward for a different starting point within the original match.  But
the ending point should NEVER be advanced further -- that's where the
"leftmost over nongreedy" rule should apply instead...

Deven


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