newbie how do I interpret this?

Mike Meyer mwm at mired.org
Sat Nov 12 12:51:30 EST 2005


bobueland at yahoo.com writes:

> Here's a small session
>
>>>> import re
>>>> p=re.compile('[a-z]+')
>>>> m=p.match('abb1a')
>>>> dir(m)
> ['__copy__', '__deepcopy__', 'end', 'expand', 'group', 'groupdict',
> 'groups', 'span', 'start']
>>>> help(m.groups)
> Help on built-in function groups:
>
> groups(...)
>
>>>>
>
> My question is. How do I interpret the hiven help info
> groups(...)
>
> alt1. Tough luck. There's no help. People are to busy to write
> reference manuals.
> alt 2. There are no parameters. The only possibility is m.groups()
> alt3. Something else

alt 3, specifically: No doc string, time to check the reference manual.

<URL: http://docs.python.org/lib/match-objects.html > says:

groups(	[default])
        Return a tuple containing all the subgroups of the match, from
        1 up to however many groups are in the pattern. The default
        argument is used for groups that did not participate in the
        match; it defaults to None. (Incompatibility note: in the
        original Python 1.5 release, if the tuple was one element
        long, a string would be returned instead. In later versions
        (from 1.5.1 on), a singleton tuple is returned in such cases.)

Since you don't have any groups in your re, groups is always going to
return (). You probably want group().

       <mike
-- 
Mike Meyer <mwm at mired.org>			http://www.mired.org/home/mwm/
Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information.



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