On Sat, 07 May 2005 08:35:21 -0700, [EMAIL PROTECTED] wrote:
> See mr Martellis comment of 2001/09/06 in mentiond recipe, you then get
> something like this
>
> -#!/usr/bin/env python
> -class Borg(object):
> - _shared_state = {}
> - def __init__(self):
> - self.__dict__ = self._shared_state
> -
> -class Duck(Borg):
> - def __init__(self):
> - super(Duck, self).__init__()
> - self.__covering = "feathers" # all ducks are feathered
What version of Python are you using? I'm using 2.3.3 and I get this:
py> donald = Duck()
Traceback (most recent call last):
File "<stdin>", line 1, in ?
File "<stdin>", line 3, in __init__
TypeError: super() argument 1 must be type, not classobj
>- self.__covering = "feathers" # all ducks are feathered
>- def covering(self):
>- return self.__covering
>-
>-class Rabbit(Borg):
>- def __init__(self):
>- super(Rabbit, self).__init__()
>- self.__covering = "fur" # all rabbits are furry
> - def covering(self):
> - return self.__covering
Hmmm... I hate to be ungrateful, but apart from being inelegant, it means
having to write get_attribute() and set_attribute() methods for every
attribute the caller might conceivably use. I'm sure to miss at least one.
*wink*
Either that or muck around with __getattr__ and __setattr__, which is
getting uglier by the minute.
I'm thinking what I might need is a function that generates a Borg-like
class. So I would do something like:
Rabbit = MakeBorgClass()
# Rabbit is now a class implementing shared state
# all instances of Rabbit share the same state
Duck = MakeBorgClass()
# Duck is now a class implementing shared state
# all instances of Duck share the same state
# but instances of Duck do not share state with instances of Rabbit
Problem is, I haven't got the foggiest idea how to implement something
like that. Am I on the right track? Where do I go from here?
Thanks,
Steven.
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