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Date: Wed, 20 Aug 1997 13:07:15 -0400 (EDT)
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From: David Bakhash <cadet@MIT.EDU>
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To: Glynn Clements <glynn@sensei.co.uk>
Cc: Pete Ware <ware@cis.ohio-state.edu>, xemacs-beta@xemacs.org
Subject: Re: New regex syntax
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Glynn Clements writes:
 > Consider matching against XYZYZ
 > 
 > 	X.*Z	==> XYZYZ
 > 	X.*?Z	==> XYZ
 > 
 > Without *? you would have to use X[^Z]*Z instead. Not in itself a big
 > deal, but if the trailing regex is more complex, then the advantages
 > become much more significant.

AFAIK, this is only true if you're using the posix REs.  in the example
above, can you really be guaranteed that X.*Z won't match XYZ using the
standard emacs RE facilities?

dave

