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Groups > comp.lang.python > #56552

Re: super in Python 3 and variadic arguments

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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

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super in Python 3 and variadic arguments Marco Buttu <marco.buttu@gmail.com> - 2013-10-09 17:44 +0200
  Re: super in Python 3 and variadic arguments Ned Batchelder <ned@nedbatchelder.com> - 2013-10-09 12:47 -0400
    Re: super in Python 3 and variadic arguments Marco Buttu <marco.buttu@gmail.com> - 2013-10-10 09:22 +0200
      Re: super in Python 3 and variadic arguments Ned Batchelder <ned@nedbatchelder.com> - 2013-10-10 07:04 -0400
        Re: super in Python 3 and variadic arguments Marco Buttu <marco.buttu@gmail.com> - 2013-10-10 14:54 +0200
        Re: super in Python 3 and variadic arguments Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-11 02:11 +0000
          Re: super in Python 3 and variadic arguments Ian Kelly <ian.g.kelly@gmail.com> - 2013-10-10 20:33 -0600
            Re: super in Python 3 and variadic arguments Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-11 03:00 +0000
              Re: super in Python 3 and variadic arguments Chris Angelico <rosuav@gmail.com> - 2013-10-11 17:08 +1100
            Re: super in Python 3 and variadic arguments Marco Buttu <marco.buttu@gmail.com> - 2013-10-11 08:17 +0200
          Re: super in Python 3 and variadic arguments Marco Buttu <marco.buttu@gmail.com> - 2013-10-11 08:15 +0200

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