[Python-Dev] PEP 309: Partial method application

Fri Aug 19 09:14:17 CEST 2005

Martin v. Löwis wrote:
> Steven Bethard wrote:
> >>I thought that:
> >> operator.attrgetter() was for obj.attr
> >> operator.itemgetter() was for obj[integer_index]
> >
> >
> > My point exactly. If we're sticking to the same style, I would expect that for
> > obj.method(*args, **kwargs)
> > we would have something like:
> > operator.methodcaller('method', *args, **kwargs)
>> You might be missing one aspect of attrgetter, though. I can have
>> f = operator.attrgetter('name', 'age')
>> and then f(person) gives me (person.name, person.age). Likewise for
> itemgetter(1,2,3).
[snip]
> I don't know what the common use for
> attrgetter is: one or more attributes?

Well, in current Python code, I'd be willing to wager that it's one,
no more, since Python 2.4 only supports a single argument to
itemgetter and attrgetter. Of course, when Python 2.5 comes out, it's
certainly possible that the multi-argument forms will become
commonplace.
I agree that an operator.methodcaller() shouldn't try to support
multiple methods. OTOH, the syntax
 methodcall.method(*args, **kwargs)
doesn't really lend itself to multiple methods either.
STeVe
-- 
You can wordify anything if you just verb it.
 --- Bucky Katt, Get Fuzzy