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Re: Should one always add super().__init__() to the __init__?

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On Sun, Sep 30, 2012 at 2:37 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> Which is exactly my point -- you can't call the superclass "just in case"
> it changes, because you don't know what arguments the new superclass or
> classes expect. You have to tailor the arguments to what the parent
> expects, and even whether or not you have to call super at all.[1]
>
> super() is not some magic command "don't bother me with the details, just
> make method overriding work". You have to actually think about what you
> are overriding.

Yeah. Far as I'm concerned, subclassing should *always* involve
knowing the parent class. You needn't concern yourself with its
implementation (I can subclass dict without caring about the details
of hash randomization), but you have to be aware of its interface. And
if you change the base class without changing your method chaining,
you'd better be changing to a new base class that's equivalent to the
old one.

The advantage of super() is that you can substitute a subclass of X as
a new base class without changing anything. But you need to be sure
that the replacement base class obeys the Liskov Substitution
Principle.

ChrisA

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Should one always add super().__init__() to the __init__? Ramchandra Apte <maniandram01@gmail.com> - 2012-09-29 06:27 -0700
  Re: Should one always add super().__init__() to the __init__? Ramchandra Apte <maniandram01@gmail.com> - 2012-09-29 06:28 -0700
  Re: Should one always add super().__init__() to the __init__? Ian Kelly <ian.g.kelly@gmail.com> - 2012-09-29 10:59 -0600
  Re: Should one always add super().__init__() to the __init__? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-29 17:17 +0000
    Re: Should one always add super().__init__() to the __init__? Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-09-29 14:18 -0400
    Re: Should one always add super().__init__() to the __init__? Chris Angelico <rosuav@gmail.com> - 2012-09-30 04:31 +1000
      Re: Should one always add super().__init__() to the __init__? Piet van Oostrum <piet@vanoostrum.org> - 2012-09-29 17:51 -0400
        Re: Should one always add super().__init__() to the __init__? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-30 04:40 +0000
          Re: Should one always add super().__init__() to the __init__? Ian Kelly <ian.g.kelly@gmail.com> - 2012-09-30 00:08 -0600
            Re: Should one always add super().__init__() to the __init__? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-30 09:34 +0000
              Re: Should one always add super().__init__() to the __init__? Manuel Pégourié-Gonnard <mpg@elzevir.fr> - 2012-09-30 14:04 +0200
      Re: Should one always add super().__init__() to the __init__? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-30 04:37 +0000
        Re: Should one always add super().__init__() to the __init__? Chris Angelico <rosuav@gmail.com> - 2012-09-30 14:53 +1000
        Re: Should one always add super().__init__() to the __init__? Ian Kelly <ian.g.kelly@gmail.com> - 2012-09-30 01:13 -0600
    Re: Should one always add super().__init__() to the __init__? Ramchandra Apte <maniandram01@gmail.com> - 2012-09-29 20:14 -0700
      Re: Should one always add super().__init__() to the __init__? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-30 04:23 +0000
        Re: Should one always add super().__init__() to the __init__? Ramchandra Apte <maniandram01@gmail.com> - 2012-09-29 21:55 -0700
          Re: Should one always add super().__init__() to the __init__? Ian Kelly <ian.g.kelly@gmail.com> - 2012-09-30 00:10 -0600

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