Why nested scope rules do not apply to inner Class?

Cousson, Benoit b-cousson at ti.com
Wed Aug 13 19:13:46 CEST 2008

> There is no point of nested classes because nested classes _are not_
> supported by python. They are simply an artifact of not actively
> denying the syntax non-globally. I would fully support a change to the
> language to actively forbid a class definition that is not
> module-level.
> > In my case, I'm trying to use a similar approach as XIST's one, meaning
> using Python class to model hierarchical data. So clearly nested class is
> a very nice and easy understandable way to do that.
> I don't find that this is clear in anyway. I can't imagine why you'd
> think a nested class is even useful here, rather than an instance with
> some understandable attributes. I've seen a lot of places nested
> classes are used and not one of them that should be been doing it.
> But, on that note, there is a point where a discussion is obviously
> not going to resolve with either side changing their minds. This is
> obviously such a case.

I don't think so; my original email was mainly a question. I do agree that they are other ways to do what I'm trying to achieve; there are always several ways to solve an issue. 
Few days ago, I decided to use nested class because I realized that it was the most convenient way to implement my need. 
Since this feature is supported in many languages, I was just surprised that Python did support it only partially, hence my original email.  

Now if you say; it is not supported, don't do that, we will deprecate that feature, fine, I will use an alternative solution. 

I was just not aware of that "nested class is evil" group in the Python community. I still not understand why, but if it is the BDFL decision...


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