Andrew We are not able to implement specialisation as I would like - true O-O would be better - so the child has all the features of the parent at the outset - though the editor knows a little about what is going on.
Try renaming - you have to specialise the concept (shadowing in O-O), but you can move it about with impunity. This should not be allowed if the archetype is ordered. Until we get an editor that can cope with specialisation in the o-o paradigm (which is well beyond my technical skill) we will have to make do with what we have. Cheers, Sam > I would only hope that that is what is intended. However, the semantics at > the moment that appears to be supported by the editor implies that archetype > specialization is nothing more that "cut and paste" style semantics. We will > have to wait for the answer from Tom and Sam. > > Also, I am wondering if archetype specialization only supports restriction > or extension or both? > > -Andrew > > > -----Original Message----- > From: owner-openehr-technical at openehr.org > [mailto:owner-openehr-technical at openehr.org] On Behalf Of Grahame Grieve > Sent: Thursday, 26 May 2005 12:08 PM > To: openehr-technical at openehr.org > Subject: Re: The semantics of archetype Specialization > > Hi Andrew > > Well, I'll defer to Tom or Sam. But from a > computational perspective, what else could make sense? > > Grahame > > > Andrew Goodchild wrote: > >>Thanks Grahame, >> >>The UML specs definition of specialization matches what I thought it had >>meant. >> >>I guess what I would like to understand is whether such a definition is > > true > >>or not for archetypes? >> >>Is specialization in archetypes meant to support the definition you > > provided > >>and the archetype editor is missing some functionality to ensure that only >>correctly specialized archetypes can be built? >> >>- or - >> >>Is it that archetypes and the editor supports some new semantics around >>specialization that I don't quite understand yet? >> >>I am sure Sam or Tom could shed some light on this ... >> >>Cheers, Andrew >> >> >>-----Original Message----- >>From: owner-openehr-technical at openehr.org >>[mailto:owner-openehr-technical at openehr.org] On Behalf Of Grahame Grieve >>Sent: Thursday, 26 May 2005 10:57 AM >>To: openehr-technical at openehr.org >>Subject: Re: The semantics of archetype Specialization >> >>Hi Andrew >> >> >> >>>Does anyone know what it actually means to specialize an archetype? And >> >>what >> >> >>>the rules are? >> >> >>The UML specification offers this definition for generalization: >> >> A taxonomic relationship between a more general element and a >> more specific element. The more specific element is fully consistent >> with the more general element and contains additional information. An >> instance of the more specific element may be used where the more >> general element is allowed >> >>I think that this is a fairly watertight definition and quite relevent >>to your question. >> >> >> >>>I looked at the archetype editor and created a specialized archetype of >>>another. The editor seemed to just copy the parent archetype and then >>>allowed the user to change anything about the archetype. >>> >>>For example, I can now make a mandatory field optional, or I can extend a >>>parent archetype with new mandatory fields that don't exist as optional >>>fields in the parent archetype >> >> >>By the UML definitions, these become "ill-formed" model. >> >>Of course, it's one thing to to state the definition, quite another to >>know how to compute whether a model is ill-formed. >> >>Grahame >> >> >> >>- >>If you have any questions about using this list, >>please send a message to d.lloyd at openehr.org > > > > > - > If you have any questions about using this list, > please send a message to d.lloyd at openehr.org > - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
