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Re: Help needed with regexps
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From: |
Stefan Monnier |
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Subject: |
Re: Help needed with regexps |
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Date: |
Fri, 13 Feb 2004 19:37:32 GMT |
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User-agent: |
Gnus/5.09 (Gnus v5.9.0) Emacs/21.3.50 |
> :front
> "<style\\s-+\\(\\s-*.*\\s-+\\)*.*css\"?\\(\\s-*.*\\s-*\\)*\\s-*>"
Regexps like A*.*B* are asking for trouble because there is an exponential
numberof ways to match them and the regexp-engine uses backtracking.
So it will get stuck trying them all, potentially for hours or even years.
To you it just looks like "it's stuck".
Stefan