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