Gunther, I will face a similar problem in the near future and would be very interested what you and others find out about this problem. I haven't looked at possible approaches myself yet, as the issue isn't a pressing one at the moment. I am not a regex expert but I have the feeling that this could be a though one. If it is feasible though, I would of course be all for adding it to ORO :-)
Best regards, Thomas > -----Original Message----- > From: Gunther Schadow [mailto:[EMAIL PROTECTED]] > Sent: Monday, March 25, 2002 4:12 PM > To: oro-user > Subject: Comparing two Regex *Patterns* > > > Hi, > > for an XSLT-based up-translation engine that I'm writing, I > am using ORO matcher. Works very well (and better than the > other two options), thanks! > > Now I wonder about the following and wanted some input from > experts on theory of regular expressions and their compilers > and matchers: is there some algebraic way of comparing two > regex patterns (not a string with a pattern, but two patterns.) > The point is to figure out if one pattern is (partially) > contained in another pattern and if strings matched by one > pattern are also matched by another pattern (i.e. the set > of strings mathing pattern 2 is a subset of the set of > strings matching pattern 1.) The use case for this is to > find ambiguities between rules using such related patterns > such that one can test these patterns in groups (or, for > XSLT, assign higher priority to the more specific pattern.) > The point is that the computer should make this analysis > not the guy who defines a transformation using many regexes. > > Generally evaluating such similarity relationships could be > fairly involved. But I think this question should be part of > any theoretical discussion of regexes, and if anyone knows > of some information about this please holler. Actually I am > just now searching through the Annals of the ACM and there > are a few pertinent articles that feel like this is a hard > problem. Anyone knows of any implementations of any of this? > Do people here feel that comparison operations between Patterns > would be a good addition to ORO (if it is feasible)? > > thanks, > -Gunther Schadow > > PS: I would appreciate if you could put my personal email > address on your replies. Thanks. > > > > -- > Gunther Schadow, M.D., Ph.D. > [EMAIL PROTECTED] > Medical Information Scientist Regenstrief Institute for > Health Care > Adjunct Assistant Professor Indiana University School > of Medicine > tel:1(317)630-7960 > http://aurora.regenstrief.org > > > > -- > To unsubscribe, e-mail: > <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: > <mailto:[EMAIL PROTECTED]> > ************************************ If this email is not intended for you, or you are not responsible for the delivery of this message to the addressee, please note that this message may contain ITT Privileged/Proprietary Information. In such a case, you may not copy or deliver this message to anyone. You should destroy this message and kindly notify the sender by reply email. Information contained in this message that does not relate to the business of ITT is neither endorsed by nor attributable to ITT. ************************************ -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
