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Why should I require all subclasses to call super() if I can use getmro to do it automatically?

I've read many of the other questions and opinions about super like super-harmful and super-considered-super but none of them mention inspect.getmro as an alternative. I'm wondering, instead of implementing a class hierarchy like this:

class Base(object):
  def __init__(self, **kwargs):
    print("base init")

class A(Base):
  def __init__(self, **kwargs):
    super(A, self).__init__()
    print("a init")

class B(Base):
  def __init__(self, **kwargs):
    super(B, self).__init__()
    print("b init")

class C(A, B):
  def __init__(self, **kwargs):
    super(C, self).__init__()
    print("c init")

Why don't we do something like this?

import inspect

class Base(object):
  def __init__(self, **kwargs):
    mro = inspect.getmro(self.__class__)

    for mro_cls in reversed(mro):
      if hasattr(mro_cls, "_init"):
        mro_cls._init(self, **kwargs)

  def _init(self, **kwargs):
    print("base")

class A(Base):
  def _init(self, **kwargs):
    print("a init")

class B(Base):
  def _init(self, **kwargs):
    print("b init")

class C(A, B):
  def _init(self, **kwargs):
    print("c init")

It seems like there are some potential benefits:

  • New developers can extend the hierarchy by implementing _init without additional boilerplate.
  • Enforce standard practices like initializing the parent class before the child for attribute overrides.

Are there any drawbacks that I'm missing?



source https://stackoverflow.com/questions/71132222/why-should-i-require-all-subclasses-to-call-super-if-i-can-use-getmro-to-do-it

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