[Python-ideas] Re: mro and super don't feel so pythonic

March 27, 2022

...
On 26 Mar 2022, at 18:15, malmiteria <martin.milon@ensc.fr> wrote:
the alternative to super really is not the important part of my proposal, it's the alternative to MRO.
An example of a case where i genuinly believe my solution adds value is this :
```
class A:
   def method(self):
       print("A")
class B:
   def method(self):
       print("B")
class C(A, B):
   pass
```
Today, a code such as ```C().method()``` works without any problems
except of course when the method you wanted to refer to was the method from B.
If class A and B both come from libraries you don't own, and for some reason have each a method named the same (named run, for example)
the run method of C is silently ignoring the run method of B.
I believe it would make the programmers life easier to have an error at this time, or anything tbh, to make explicit this resolution, because it really is not explicit from most programmers perspective
my alternative to super comes to fit the alternative to mro, i think it stills matter to have a dedicated feature instead of simply calling class.method, this allows for more error handling and stuff like that, in case for example you're calling super on a class that's not a parent for example, since super really is for accessing parents context.
This is not so much about final code, but more about making it easier *when* writing code. But the final code would definitely not look that much prettier / ugglier, I agree
And finally, super is not a proxy to parents, even plural, it's a proxy to the next in mro order.
in this case :
class Top:
   def method(self):
       print('Top')
class Left(Top):
   def method(self):
       print('Left')
       super().method()
class Right(Top):
   def method(self):
       print('Right')
       super().method()
class Bottom(Left, Right):
   def method(self):
       print('Bottom')
       super().method()
Bottom().super() would print "Bottom", "Left", "Right", "Top".
super, in Left, reffers to Right, which is not a parent of Left (and is completely absent of it's definition)
My feeling is that if I was doing a code review of this sort of code I would be raising two possible issues.
1) You have a class that does more than 1 thing. That is an OO code smell. Use composition to avoid.
2) If you have a parent class that has a method that conflicts then I would say that you need to
add a facade to allow one of the conflicting method names to be accessed via another name.

For example

Class FacadeB(B):
	def method_in_B(self, *args, **kwds):
		B.method(self, *args, **kwds)

Barry
...
Anyways, i'm called to a pub, i'll talk to you guys more tomorrow, have a great night
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[Python-ideas] Re: mro and super don't feel so pythonic

Barry Scott