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From: Marco Buttu <marco.buttu@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: super in Python 3 and variadic arguments
Date: Thu, 10 Oct 2013 09:22:00 +0200
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Xref: csiph.com comp.lang.python:56552

On 10/09/2013 06:47 PM, Ned Batchelder wrote:

>> >>> class B(A):
>> ...     def bfoo(*args):
>> ...         super().afoo(*args[1:])
>> ...
>> >>> B().bfoo(1, 2, 3)
>> Traceback (most recent call last):
>>   File "<stdin>", line 1, in <module>
>>   File "<stdin>", line 3, in bfoo
>> RuntimeError: super(): no arguments
>>
>> How come?
>
> The no-args super() call inspects the calling environment to determine
> the class and self.  "self" is the first local name stored in
> frame.f_code.co_localsplus, but *args doesn't put "args" into that entry
> of the code object

But is it a bug or the behavior we want? The first (implicit) argument 
is stored as expected as the first one in the args tuple, and the args 
tuple is inserted as expected in frame.f_locals:

 >>> import inspect
 >>> class B(A):
...     def bfoo(*args):
...         frame = inspect.currentframe()
...         for obj, value in frame.f_locals.items():
...             print(obj, value, sep=' --> ')
...         # super().afoo(*args[1:])
...
 >>> B().bfoo(1, 2, 3)
args --> (<__main__.B object at 0x7f28c960a590>, 1, 2, 3)
frame --> <frame object at 0x7f28cad4b240>

So, why does not super use it?

-- 
Marco Buttu