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From: Alan Mackenzie <acm@muc.de>
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Subject: Re: Progressively slow pattern match
Date: Wed, 17 May 2006 20:00:18 +0000 (GMT)
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On Wed, 17 May 2006, Ralf Angeli wrote:

>* David Kastrup (2006-05-17) writes:

>> Ralf Angeli <angeli@caeruleus.net> writes:

>>> (looking-at "\\(%+\\)*foo")
>[...]
>>> Is this a deficiency in Emacs?  Is there a way matching can be sped up
>>> with this or maybe another, equivalent regexp?

>> Uh, "\\(%+\\)?foo" maybe?

>The original regexp looks something like
>"\\(%+[ \t]*\\)*foo"
>in order to match stuff like
>%% %% %% foo

Use "\\(%+[ \t]+\\)%*foo"
               ^
instead

>Ralf

-- 
Alan.