Steve Spicklemire wrote:
Hi Folks,
The Dumb ZPatterns example is updated. Now there is some more realistic object referencing going on, borrowing of code snippets between Specialists and suchlike. There is also more in the way of reasonable documentation, though everything is in flux, and it still doesn't resemble a truly completed product. I just feel the need to get things finished enough that I can stop thinking about them for a while. ;-) In particular there the ToDos now hold references to Doer and Deliverable, and no 'lists' are maintained. One thing I need to do is to have these references automatically 'fixed' when a 'referred to' entity is removed or modified in such a way that the link should be broken.... that's for the next version. If I'm not careful.. it won't be a 'simple' example anymore. There's got to be a line here somewhere (in the sand?).
Nice work, Steve. Removing id lists looks good. I started building objects using getXForY(y_id), but the last one I made used an id list following the Dumb Example. I've just changed it to use getXForY, and it's much cleaner, plus it makes adding X from Y/editInstanceForm easier. I like the idea of naming all UI methods with '_html' - now, if you find yourself referencing a method which doesn't end in '_html' in your html code, you know you need to add an interface method. I just need to decide if I like it enough to change all my existing code... Some thoughts about the broken links handling problem: If an object depends on the existence of another (for example, if you wanted a ToDo to be tightly linked to a Deliverable) then it should be deleted when the Deliverable is deleted, right? You'd have WHEN OBJECT DELETED CALL ToDos.deleteInstances(myToDoIDs) in the Deliverable SkinScript, and you would never have ToDos floating around without a Deliverable. As for the Deliverable changing and invalidating the link, I think it would be solved if you used immutable ids for all objects, and stored the Deliverable title in a separate property. In case of weaker links, such as between ToDo and Doer, I guess it should be ToDo's responsibility to return None if the Doer referenced by doerID doesn't exist - treating it the same way as the case where no doer has been assigned. Maybe with this SkinScript: WITH Doers.getItem(self.doerID) CALCULATE self.doerID=RESULT.id or '' ? But I'm not really sure about this... I think you've managed very well to stay on the right side of the line in the sand... the problem is that complex real world applications have a lot of stuff on the other side of the line, and the challenge is to pull that stuff over the line. My personal problem is figuring out if the stuff I have on the wrong side of the line is necessitated by the complexity of the application, or if I'm just making things unnecessarily complicated... Itai -- Itai Tavor "Je sautille, donc je suis." C3Works itai@c3works.com - Kermit the Frog "If you haven't got your health, you haven't got anything"