Prothon Prototypes vs Python Classes
Andrew Bennetts
andrew-pythonlist at puzzling.org
Sat Mar 27 23:04:17 EST 2004
On Sun, Mar 28, 2004 at 03:37:25AM +0000, Joe Mason wrote:
[...]
>
> Ed Suominen just posted a situation where classes and instances need to
> be treated separately. He has a class, "AutoText", with various
> subclasses (which I'll call "AutoA", "AutoB", etc. because I forget the
> details). He wants to notice whenever somebody creates a subclass of
> AutoText and add it to a list so that he can have an AutoAll function
> which creates just one instance of each. (Or something like that.)
>
[...]
> In Python, the easiest way to do this is with metaclasses, which is a
> really advanced topic. In Prothon, it's simple to "notice" when a
> subclass is created, because __init__ gets called! So you just say:
Actually, in Python, it's even easier than that:
>>> class C(object): pass
...
>>> class D(C): pass
...
>>> C.__subclasses__()
[<class '__main__.D'>]
-Andrew.
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