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Re: Python's super() considered super!

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sturlamolden <sturlamolden@yahoo.no> wrote:

> On 26 Mai, 18:31, Raymond Hettinger <pyt...@rcn.com> wrote:
>> I just posted a tutorial and how-to guide for making effective use of
>> super().
>>
>> One of the reviewers, David Beazley, said, "Wow,  that's really
>> great!    I see this becoming the definitive post on the subject"
>>
>> The direct link is:
>>
>>  http://rhettinger.wordpress.com/2011/05/26/super-considered-super/
> 
> I really don't like the Python 2 syntax of super, as it violates
> the DRY principle: Why do I need to write super(type(self),self)
> when super() will do? Assuming that 'self' will always be named
> 'self' in my code, I tend to patch __builtins__.super like this:
> 
> import sys
> def super():
>     self = sys._getframe().f_back.f_locals['self']
>     return __builtins__.super(type(self),self)
> 
> This way the nice Python 3.x syntax can be used in Python 2.x.
> 
> 
Oh dear, you haven't thought this one through.

After your code above, try this:

>>> class A(object):
	def foo(self):
		print "A.foo"

		
>>> class B(A):
	def foo(self):
		print "B.foo"
		super().foo()

>>> B().foo()
B.foo
A.foo

So far so good.
Now try this:

>>> class C(B): pass

>>> C().foo()
... infinite recursion follows ...

Oops. There's a reason why Python 2 requires you to be explicit about 
the class; you simply cannot work it out automatically at run time. 
Python 3 fixes this by working it out at compile time, but for Python 2 
there is no way around it.


-- 
Duncan Booth http://kupuguy.blogspot.com

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Python's super() considered super! Raymond Hettinger <python@rcn.com> - 2011-05-26 09:31 -0700
  Re: Python's super() considered super! Raymond Hettinger <python@rcn.com> - 2011-05-26 09:39 -0700
    Re: Python's super() considered super! Dotan Cohen <dotancohen@gmail.com> - 2011-05-26 21:13 +0300
    Re: Python's super() considered super! Ian Kelly <ian.g.kelly@gmail.com> - 2011-05-26 12:38 -0600
    Re: Python's super() considered super! Dotan Cohen <dotancohen@gmail.com> - 2011-05-26 21:56 +0300
    Re: Python's super() considered super! Terry Reedy <tjreedy@udel.edu> - 2011-05-26 16:15 -0400
  Re: Python's super() considered super! Ben Finney <ben+python@benfinney.id.au> - 2011-05-27 11:39 +1000
    Re: Python's super() considered super! Raymond Hettinger <python@rcn.com> - 2011-05-27 00:16 -0700
      Re: Python's super() considered super! Ben Finney <ben+python@benfinney.id.au> - 2011-05-27 18:49 +1000
        Re: Python's super() considered super! Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-05-27 10:37 +0000
          Re: Python's super() considered super! Duncan Booth <duncan.booth@invalid.invalid> - 2011-05-27 10:53 +0000
            Re: Python's super() considered super! Ethan Furman <ethan@stoneleaf.us> - 2011-05-27 10:42 -0700
              Re: Python's super() considered super! Duncan Booth <duncan.booth@invalid.invalid> - 2011-05-30 09:18 +0000
    RE: Python's super() considered super! "Prasad, Ramit" <ramit.prasad@jpmchase.com> - 2011-05-27 14:10 -0400
    Re: Python's super() considered super! Chris Angelico <rosuav@gmail.com> - 2011-05-28 04:40 +1000
  Re: Python's super() considered super! sturlamolden <sturlamolden@yahoo.no> - 2011-05-27 07:27 -0700
    Re: Python's super() considered super! Mel <mwilson@the-wire.com> - 2011-05-27 10:33 -0400
      Re: Python's super() considered super! Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-05-27 14:49 +0000
        Re: Python's super() considered super! harrismh777 <harrismh777@charter.net> - 2011-05-27 10:07 -0500
    Re: Python's super() considered super! Duncan Booth <duncan.booth@invalid.invalid> - 2011-05-27 15:05 +0000
      Re: Python's super() considered super! sturlamolden <sturlamolden@yahoo.no> - 2011-05-27 08:24 -0700
      Re: Python's super() considered super! sturlamolden <sturlamolden@yahoo.no> - 2011-05-27 08:31 -0700
        Re: Python's super() considered super! Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-05-27 16:06 +0000
          Re: Python's super() considered super! Stefan Behnel <stefan_ml@behnel.de> - 2011-05-27 23:49 +0200
            Re: Python's super() considered super! sturlamolden <sturlamolden@yahoo.no> - 2011-05-27 16:57 -0700
              Re: Python's super() considered super! Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2011-05-28 07:29 +0200
          Re: Python's super() considered super! sturlamolden <sturlamolden@yahoo.no> - 2011-05-27 17:04 -0700
      Re: Python's super() considered super! Ryan Kelly <ryan@rfk.id.au> - 2011-05-28 09:57 +1000
    Re: Python's super() considered super! sturlamolden <sturlamolden@yahoo.no> - 2011-05-27 08:11 -0700
  Re: Python's super() considered super! Ian Kelly <ian.g.kelly@gmail.com> - 2011-05-27 12:31 -0600
  Re: Python's super() considered super! Chris Angelico <rosuav@gmail.com> - 2011-05-28 04:46 +1000
    Re: Python's super() considered super! John Nagle <nagle@animats.com> - 2011-05-27 13:47 -0700
  Re: Python's super() considered super! Ethan Furman <ethan@stoneleaf.us> - 2011-05-27 15:24 -0700

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