Hi Itai,
"Itai" == Itai Tavor <itai@optusnet.com.au> writes:
Itai> Say I got several Participants, and some of those need to be Itai> able to place orders. I create the Specialist Itai> OrderingEntities to implement the role of 'someone who Itai> places orders'. From what I understand about using Itai> Specialists to extend a class behavior, this Specialist Itai> should add the properties it needs to track orders with to Itai> the Participant classes - I should not have to go in to Itai> every Participant class and add the property to it, because Itai> those classes don't know and don't care that they might be Itai> used in this role. Am I wrong in this? Otherwise, the only Itai> other way to track properties for this role would be to Itai> physically store a new object on the OrderingEntities Rack Itai> for every Participant class accessed, but what's the point Itai> in that, if I can simply add the property to the original Itai> class? No.. you're right here. I've never used property sheets in this way, just because it's seemed too much trouble to check for existence, then add if necessary... etc. If I need to have a property set in an instance... I just set it, using an external method. (Or I add it at the ZClass level.) It's important to be careful though... if there is already a property with that name.... there could be a clash. Obviously application integration needs to be done with full awareness of the different attributes used by each component. Itai> Making small steps up the ZPatterns mountain (and too many Itai> of them backwards), Yup.. me too. ;-) But it's better than sticks and bones.. take care, -steve Itai> Itai -- Itai Tavor "Je sautille, donc je suis." C3Works Itai> itai@c3works.com - Kermit the Frog Itai> "If you haven't got your health, you haven't got anything"