match groups: optional groups not accessible
peter at engcorp.com
Fri Jun 10 19:03:41 CEST 2005
Peter Hansen wrote:
> david.reitter at gmail.com wrote:
>> Why does the following result in an IndexError?
>> I try to match an optional group, and then access it via its group
>> name. The group happens to not participate in the match, but is
>> obviously defined in the pattern.
>>>>> m = re.match('(?P<m>maybe)?yes', "yes")
> Uh, don't you need to actually *group* the first "yes" part, with
> parentheses, to make it a group? Otherwise you aren't going to be
> treating it as other than text-between-groups-that-can-be-skipped.
Oops... from Duncan's reply and a reread I can see I missed the point
entirely... I obviously thought you were expecting the "yes" to be in a
group too. Duh.
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