[Python-Dev] python and super

[Ricardo Kirkner]

Exactly what Michael said. Stopping the chain going upwards is one
thing. Stopping it going sideways is another.

On Thu, Apr 14, 2011 at 12:37 PM, Michael Foord
<fuzzyman at voidspace.org.uk> wrote:
> On 14/04/2011 16:34, P.J. Eby wrote:
>>
>> At 03:55 PM 4/14/2011 +0100, Michael Foord wrote:
>>>
>>> Ricardo isn't suggesting that Python should always call super for you,
>>> but when you *start* the chain by calling super then Python could ensure
>>> that all the methods are called for you. If an individual method doesn't
>>> call super then a theoretical implementation could skip the parents
>>> methods (unless another child calls super).
>>
>> That would break classes that deliberately don't call super.  I can think
>> of examples in my own code that would break, especially in __init__() cases.
>>
>> It's perfectly sensible and useful for there to be classes that
>> intentionally fail to call super(), and yet have a subclass that wants to
>> use super().  So, this change would expose an internal implementation detail
>> of a class to its subclasses, and make "fragile base class" problems worse.
>>  (i.e., where an internal change to a base class breaks a previously-working
>> subclass).
>
> It shouldn't do. What I was suggesting is that a method not calling super
> shouldn't stop a *sibling* method being called, but could still prevent the
> *parent* method being called.
>
> Michael
>
> --
> http://www.voidspace.org.uk/
>
> May you do good and not evil
> May you find forgiveness for yourself and forgive others
> May you share freely, never taking more than you give.
> -- the sqlite blessing http://www.sqlite.org/different.html
>
>