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Re: Updated blog post on how to use super()

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On 6/1/2011 12:42 PM, Ian Kelly wrote:
> On Wed, Jun 1, 2011 at 7:03 AM, Billy Mays<noway@nohow.com>  wrote:
>> I read this when it was on HN the other day, but I still don't see what is
>> special about super().  It seems (from your post) to just be a stand in for
>> the super class name?  Is there something special I missed?
>
> It's not a stand-in for the super-class name.  It's a stand-in for
> whatever class is next in the Method Resolution Order (MRO), which is
> determined at run-time and can vary depending on what the actual class
> of the object is.  For example, in this inheritance situation:
>
> class A(object):
>      ...
>
> class B(object):
>      ...
>
> class C(A, B):
>      ...
>
> a = A()
> c = C()
>
> The MRO of A is (A, object).
> The MRO of B is (B, object).
> The MRO of C is (C, A, B, object).
>
> Thus, super(A, a) is going to resolve to object, as you might expect.
> But super(A, c) is going to resolve to B, because the next class after
> A in the MRO for C instances is B.
>
> That's a pretty quick and dirty explanation.  If it doesn't make
> sense, I suggest reading the article again.

What it does is clear to me, but why is it interesting or special isn't. 
  This looks like a small feature that would be useful in a handful of 
cases.

--
Bill

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Updated blog post on how to use super() Raymond Hettinger <python@rcn.com> - 2011-05-31 19:44 -0700
  Re: Updated blog post on how to use super() Ben Finney <ben+python@benfinney.id.au> - 2011-06-01 14:26 +1000
  Re: Updated blog post on how to use super() Billy Mays <noway@nohow.com> - 2011-06-01 09:03 -0400
    Re: Updated blog post on how to use super() Ian Kelly <ian.g.kelly@gmail.com> - 2011-06-01 10:42 -0600
      Re: Updated blog post on how to use super() Billy Mays <noway@nohow.com> - 2011-06-01 12:46 -0400
        Re: Updated blog post on how to use super() Ian Kelly <ian.g.kelly@gmail.com> - 2011-06-01 11:06 -0600
        Re: Updated blog post on how to use super() Chris Torek <nospam@torek.net> - 2011-06-01 17:43 +0000
    Re: Updated blog post on how to use super() Duncan Booth <duncan.booth@invalid.invalid> - 2011-06-02 20:58 +0000

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