[Python-Dev] Re: "groupby" iterator

Raymond Hettinger python at rcn.com
Wed Dec 3 10:27:49 EST 2003

> (This thread has nothing to do with the groupby iterator any more, but
> I'm loathe to change the subject since so many messages are already
> under this one.)
> (I've read quite a few messages posted after Greg's post, but Greg
> still summarizes the issue best for me, *and* it has an alternative
> idea that needs a response.)

I'm am still curious to hear your thoughts on the either sublime or
crazy idea for a generalized extractor object:

list.sorted(students, key=extract.score)
list.sorted(animal_weights, key=extract[1])
groupby(students, key=extract.homeroom)
groupby(recordtuples, key=extract[0])

Raymond Hettinger

P.S.  The implementation code is very simple:

class ExtractorClass(object):
    def __getattribute__(self, attr):
        return operator.attrgetter(attr)
    def __getitem__(self, key):
        return operator.itemgetter(key)

extract = ExtractorClass()

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