From: Robert Klemme <shortcutter@...>
Date: 2007-08-03T22:49:47+09:00
Subject: Re: Determining the common prefix for several strings

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2007/8/3, Daniel DeLorme <dan-ml@dan42.com>:
> Robert Klemme wrote:
> > I believe you are wrong.  Look at "\A(.*).*" - there are multiple ways
> > this can match (including matching \n inside any of the .* parts).
> > Anchoring does not help much here IMHO.
>
> Yes, there is backtracking for the first part (there has to be, the
> whole point being to find the longest matching string), but \n CANNOT
> match inside any of the .* parts unless you specify the m modifier.

Correct.  I always confuse Ruby's /m with other language's variants.
Thanks for the reeducation!

Still it would be interesting to do benchmarks with larger numbers of
words to see what happens....  I have attached a test. It seems the RX
approach is faster very long.

Kind regards

robert

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