Q? Calling nearest inherited method

[Fred Gansevles]

In article <3923af51.3872163586 at news.u-psud.fr>,
  pointal at lure.u-psud.fr wrote:
> On Wed, 17 May 2000 18:37:00 GMT, Guido van Rossum <guido at python.org>
> wrote:
>
> >: There's a better way.  (I believe Jeremy Hylton first suggested
this; he saw
> >: it as an idiom in another language:)
> >:
> >: class C(B):
> >:     super_doit = B.doit
> >:     def doit(self, arg):
> >:         self.super_doit(arg)
> >:
> >: This avoids the need to explicitly pass self.
>
> Not sure its really better...
> 1) The lowest problem: you have to define it for each function in each
> class in the hierarchy to have a clean model.
> 2) The biggest problem, it can go into infinite recursion...
>
> Here is an example of the biggest problem:
>
> >>> class A :
> ...     def dothis(self) :
> ...             print "In A.dothis."
> ...
> >>> class B(A) :
> ...     super_dothis = A.dothis
> ...
> >>> class C(B) :
> ...     super_dothis = B.dothis
> ...     def dothis(self) :
> ...             print "In C.dothis."
> ...             self.super_dothis()
> ...
> >>> c=C()
> >>> c.dothis()
> In C.dothis.
> In A.dothis.
>
> [Until here, its well. Now, introduce a new D subclass, and as we have
> done for B, implement the super_dothis...]
>
> >>> class D(C) :
> ...     super_dothis = C.dothis
> ...     def hello(self) :
> ...             self.dothis()
> ...
> >>> d=D()
> >>> d.hello()
> In C.dothis.
> In C.dothis.
> In C.dothis.
> In C.dothis.
> In C.dothis.
> In C.dothis.
> In C.dothis.
> ...
> [here hitting ctrl-C]
>
> So I will still with the <parentClass>.<method>(self...) usage which
> works.

An intermediate approach could be:

def super(self):
    return self.__class__.__bases__[0]

class D(C):
    def hello(self):
        super(self).dothis(self)

>
> Thanks.
>
> A+
>
> Laurent.
>
> ---
> Laurent POINTAL - CNRS/LURE - Service Informatique Experiences
> Tel/fax: 01 64 46 82 80 / 01 64 46 41 48
> email  : pointal at lure.u-psud.fr  ou  lpointal at planete.net
>

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