2001 Enchancement Wishlist
fredrik at effbot.org
Fri Dec 29 16:31:29 EST 2000
Raymond Hettinger wrote:
> 3. __init__ is the only special method that doesn't allow a return value.
> I think it should continue to return the new object by default but also
> allow another return item to be substituted. For example:
> def __init__( self ):
> if MyClass.aSingleton == None:
> MyClass.aSingleton = self
> return MyClass.aSingleton
doesn't make sense: __init__ *initializes* an instance
object, it doesn't create a new one.
if you still think creating new objects just to throw them
away really is a good idea, I'd rather see the return value
check changed from
value = self.__init__(*args, **kwargs)
assert value is None
assert value is None or isinstance(value, self.__class__)
assert value is None\
or isinstance(value, types.InstanceType)\
and value.__class__ is self.__class
allowing an arbitrary value (as long as it's not None) seems
like a really unpythonic idea.
(fwiw, singleton classes are pretty unpythonic too. python
already has a framework for creating exactly one instance of
something: the module namespace).
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