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What is the semantics meaning of 'object'?

Chris Angelico rosuav at gmail.com
Tue Jun 25 18:39:47 EDT 2013 
On Wed, Jun 26, 2013 at 8:25 AM, Ian Kelly <ian.g.kelly at gmail.com> wrote:
> On Tue, Jun 25, 2013 at 4:17 PM, Chris Angelico <rosuav at gmail.com> wrote:
>> 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?
>
> class BlackHole(object):
>     def __getattr__(self, attr):
>         return lambda *args, **kwargs: None
>
> There's no way to restrict it to just methods, because there's no
> fundamental difference in Python between methods and other attributes,
> and at the point that you're looking it up you have no way of knowing
> whether the result is about to be called or not.

Right, but what I mean is that you don't need any sort of
special-casing to pick an object type to return. Just return a
function, because that's going to be safe.

> And even if there were, this would be an excellent way to hide bugs.

Ehh, true. Don't know a way around that one. Meh.

ChrisA
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