73 lines
1.4 KiB
Org Mode
73 lines
1.4 KiB
Org Mode
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#+TITLE: Python mixins
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#+TAGS: python,coding
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I learned something fun the other day. And it has made me consider
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writing more mixins and using Python's multiple inheritance more. This
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is not completely new to me, but I finally tested it a few days ago
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and what I thought I knew seems to have been confirmed.
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Given some classes:
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#+NAME: setup
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#+BEGIN_SRC python :exports code :results output :session
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class Foo(object):
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def frob(self):
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print('foo')
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class Bar(Foo):
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def frob(self):
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super(Bar, self).frob()
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print('bar')
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class BazMixin(object):
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def frob(self):
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super(BazMixin, self).frob()
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print('baz')
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class Unmixed(Bar, BazMixin):
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def frob(self):
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super(Unmixed, self).frob()
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print('unmixed')
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class Mixed(BazMixin, Bar):
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def frob(self):
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super(Mixed, self).frob()
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print('mixed')
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#+END_SRC
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#+RESULTS: setup
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We can see the progression of inheritance. You will see here that
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=BazMixin= is skipped:
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#+NAME: unmixed
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#+BEGIN_SRC python :exports both :results output :session
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unmixed = Unmixed()
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unmixed.frob()
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#+END_SRC
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#+RESULTS: unmixed
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:
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: foo
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: bar
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: unmixed
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And here that it is not:
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#+NAME: mixed
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#+BEGIN_SRC python :exports both :results output :session
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mixed = Mixed()
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mixed.frob()
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#+END_SRC
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#+RESULTS: mixed
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:
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: foo
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: bar
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: baz
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: mixed
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