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[doc] Teach 0-args form of super in Programming FAQ (GH-22176)

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Andre Delfino 2020-09-20 14:09:50 -03:00 committed by GitHub
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@ -1504,20 +1504,19 @@ Most :meth:`__setattr__` implementations must modify ``self.__dict__`` to store
local state for self without causing an infinite recursion.
How do I call a method defined in a base class from a derived class that overrides it?
--------------------------------------------------------------------------------------
How do I call a method defined in a base class from a derived class that extends it?
------------------------------------------------------------------------------------
Use the built-in :func:`super` function::
class Derived(Base):
def meth(self):
super(Derived, self).meth()
super().meth() # calls Base.meth
For version prior to 3.0, you may be using classic classes: For a class
definition such as ``class Derived(Base): ...`` you can call method ``meth()``
defined in ``Base`` (or one of ``Base``'s base classes) as ``Base.meth(self,
arguments...)``. Here, ``Base.meth`` is an unbound method, so you need to
provide the ``self`` argument.
In the example, :func:`super` will automatically determine the instance from
which it was called (the ``self`` value), look up the :term:`method resolution
order` (MRO) with ``type(self).__mro__``, and return the next in line after
``Derived`` in the MRO: ``Base``.
How can I organize my code to make it easier to change the base class?