On Monday 05 October 2009, MRAB wrote: > You're currently looking for one that's not followed by another; > the solution is to check first whether there are two: > > >>> re.match(r'(?!.*?C1.*?C1)(.*?C1)','C1b1b1b1 b3b3b3b3 > C1C2C3').groups() > > Traceback (most recent call last): > File "<pyshell#3>", line 1, in <module> > re.match(r'(?!.*?C1.*?C1)(.*?C1)','C1b1b1b1 b3b3b3b3 > C1C2C3').groups() AttributeError: 'NoneType' object has no > attribute 'groups'
that is a nice solution! now to make it more similar to my real world case where C1 is actually part of the string: same regex but using a group for C1 does not work - why? >>> re.match(r'(?!.*?(C1).*?\1)(.*?\1)','C1b1b1b1 b3b3b3b3 C2C2C3').groups() Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'NoneType' object has no attribute 'groups' >>> re.match(r'(?!.*?(?P<tile>C1).*?(?P=tile))(.*?(?P=tile))','C1B1B1B1 >>> b3b3b3b3 C2C2C3').groups() Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'NoneType' object has no attribute 'groups' -- Wolfgang -- http://mail.python.org/mailman/listinfo/python-list
