Marc Aymerich wrote: > Hi all, > I want to provide an encapsulated static attribute called _registry > for several classes. > > I try to use inheritance in order to make it DRY: all classes inherit > from a BaseClass that implements the _registry encapsulation. But with > inheritance it doesn't work how I want, because a single instance of > the _registry is shared between all of the inherited classes, and I > want to have an independent _registry for every class. > > How can I do that without coping all the code in every class?
If you want to go fancy use a metaclass: >>> class Base(object): ... class __metaclass__(type): ... def __init__(self, *args): ... type.__init__(self, *args) ... self.per_class = [] ... >>> class A(Base): pass ... >>> A().per_class is A().per_class True >>> class B(Base): pass ... >>> B().per_class is B().per_class True >>> A().per_class is B().per_class False -- http://mail.python.org/mailman/listinfo/python-list
