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Groups > comp.lang.python > #73174
| From | Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> |
|---|---|
| Newsgroups | comp.lang.python |
| Subject | Re: Python's re module and genealogy problem |
| Date | 2014-06-11 15:55 +0200 |
| Organization | A not so newly installed InterNetNews server |
| Message-ID | <ln9n4b$pog$1@r01.glglgl.de> (permalink) |
| References | <bvr01iFu926U1@mid.individual.net> |
Am 11.06.2014 14:23 schrieb BrJohan:
> Can it, for a pair of regular expressions be decided whether at least
> one string matching both of those regular expressions, can be constructed?
>
> If it is possible to make such a decision, then how? Anyone aware of an
> algorithm for this?
Just a feeling-based statement: I don't think that is easily possible.
Every RE can potentially match an infinite number of statements.
Just have a look at
re1 = re.compile('A43.*')
re2 = re.compile('.*[0-9][A-F]')
It can easily seen that the area these REs work on is different; they
are orthogonal.
So there is an infinite number of strings these REs match.
Thomas
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Python's re module and genealogy problem BrJohan <brjohan@gmail.com> - 2014-06-11 14:23 +0200
Re: Python's re module and genealogy problem Robert Kern <robert.kern@gmail.com> - 2014-06-11 14:26 +0100
Re: Python's re module and genealogy problem Mark H Harris <harrismh777@gmail.com> - 2014-06-11 09:08 -0500
Re: Python's re module and genealogy problem Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2014-06-11 15:55 +0200
Re: Python's re module and genealogy problem Michael Torrie <torriem@gmail.com> - 2014-06-11 09:34 -0600
Re: Python's re module and genealogy problem Nick Cash <nick.cash@npcinternational.com> - 2014-06-11 16:21 +0000
Re: Python's re module and genealogy problem Simon Ward <simon@bleah.co.uk> - 2014-06-11 18:21 +0100
Re: Python's re module and genealogy problem Vlastimil Brom <vlastimil.brom@gmail.com> - 2014-06-11 20:09 +0200
Re: Python's re module and genealogy problem BrJohan <brjohan@gmail.com> - 2014-06-13 17:17 +0200
Re: Python's re module and genealogy problem Peter Otten <__peter__@web.de> - 2014-06-13 18:26 +0200
Re: Python's re module and genealogy problem Dan Sommers <dan@tombstonezero.net> - 2014-06-14 05:14 +0000
Re: Python's re module and genealogy problem Tony the Tiger <tony@tiger.invalid> - 2014-06-14 08:35 +0000
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