Maric Michaud wrote: > Le lundi 26 juin 2006 22:37, [EMAIL PROTECTED] a écrit : > > Won't work because there will be employers that aren't workers. > > And yes, only some workers will become employers, but also only some > > employers will also be workers (at some point in program). Let me be > > more clear: > > > > workers > > --> subset of workers --become--> employers > > employers > > --> subset of employers --become--> workers > > > > It is very important that both should maintain attribute values, > > regardless of whether they take on new "roles". Furthermore, this is a > > very simple case and ultimately in my program an object should be able > > to dynamically take on a multitude of roles (classes of behavior) > > without mucking at all with their pre-existing states. > > This seem to be a OO design problem and you clearly make a misuse of > inheritance, if a person can eventually have many roles, but doesn't have > this role for all his lifetime, then the person *is* not his roles. > That the meaning of inheritance, class B(A) means a B is a A. > The association between a person and his roles is obviously a 1-n association, > which can be rendered by different patterns (delegation, composition, > strategy, etc.). > You should google on "design patterns" and make your choice.
A misuse of inheritance eh? Inheritance, like other language features, is merely a tool. I happen to be using this tool to have my virtual persons change roles at different points in their lifetime, as many real people tend to do. Thus, at these points, B is indeed an A. What a person is, whether in real life or in my program, is not static and comes into definition uniquely for each moment (micro-moment, etc.) of existence. Now, please, I have no intention of carrying the conversation in such a silly direction, I wasn't inviting a discussion on philosophy or some such. I seek to work the tools to my needs, not the other way around. > > -- > _____________ > > Maric Michaud > _____________ > > Aristote - www.aristote.info > 3 place des tapis > 69004 Lyon > Tel: +33 426 880 097 -- http://mail.python.org/mailman/listinfo/python-list
