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Date: Wed, 26 Jun 2013 12:56:29 +0200
From: Antoon Pardon <antoon.pardon@rece.vub.ac.be>
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Subject: Re: What is the semantics meaning of 'object'?
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Xref: csiph.com comp.lang.python:49247

Op 26-06-13 00:27, Mark Janssen schreef:
>> The main problem is getting to the top/end of the call chain. Classic
>> example is with __init__, but the same problem can also happen with
>> other calls. Just a crazy theory, but would it be possible to
>> construct a black-holing object that, for any given method name,
>> returns a dummy function that ignores its args? (Other forms of
>> attribute lookup aren't going to be a problem, I think, so this can be
>> just methods/functions.) Then you just subclass from that all the
>> time, instead of from object itself, and you should be able to safely
>> call super's methods with whatever kwargs you haven't yourself
>> processed. Would that work?
>>
>> Caveat: I have not done much with MI in Python, so my idea may be
>> complete balderdash.
> Here's how it *should* be made:  the most superest, most badassed
> object should take care of its children.  New instances should
> automatically call up the super chain (and not leave it up to the
> subclasses), so that the parent classes can take care of the chil'en.
>  When something goes wrong the parent class has to look in and see
> what's wrong.
Could you explain why you think it should work this way? Maybe illustrate
how this is supposed to work.

Let take a very simple example. We have a class that works with a stream
(anything with a write method).

class Streamer:
    def __init__(self, strm):
        ...

Now we find that we very often use this class with a file, so we would
like to make a subclass that takes a filename as parameter. This we would 
write somehow like the following

class Filer(Streamer):
    def __init__(self, fn):
        fl = open(fn, "a+")
        super.__init__(fl)
        ...


Can you explain how this example should be written en work as you view things?