+1 to Grahame comments. - Pablo.
> Date: Fri, 23 Mar 2012 12:12:04 +1100 > Subject: Re: Suggestion to replace use of generics with inheritence in future > RM versions > From: grahame at healthintersections.com.au > To: openehr-technical at lists.openehr.org > > Generally, you can do things in specifications that can't be > reproduced in actual implementations. > Since there is one specification, but many implementations, the list > of things that the specification > contains that aren't easy to implement varies widely between implementations. > The things that are hard to implement are sometimes also very useful > for expressing meaning > and purpose. So a good specification balances between using things > that are useful without > using things that are too hard to use. > > With regard to generics, my normal implementation contexts do not > support generics (XML/XSD, old > versions of various languages), but I still find them useful in the > specifications and would prefer > the specification expressed itself cleanly > > Grahame > > On Fri, Mar 23, 2012 at 11:51 AM, Peter Gummer > <peter.gummer at oceaninformatics.com> wrote: > > David Moner wrote: > > > >> I was exaclty thinking about this while seeing this proposal for the > >> ITEM_STRUCTURE change to a VALUE_CLUSTER: > >> > >> http://www.openehr.org/wiki/display/spec/openEHR+2.x+RM+proposals+-+lower+information+model#openEHR2.xRMproposals-lowerinformationmodel-CandidateA.1AddVALUECLUSTER%2CRemoveITEMSTRUCTUREtypes > >> > >> It is an example of multiple inheritance not supported by Java and some > >> other languages. > > > > > > Multiple inheritance is easily implemented in Java and C# ... via > > interfaces. > > > > The problem is that you often need to duplicate code. For example, in that > > diagram, VALUE_CLUSTER inherits from both ELEMENT and CLUSTER. In C# you > > can't do that, so you would probably declare ValueCluster as implementing > > two interfaces, IElement and ICluster; then you would copy the > > implementations of Element and Cluster into ValueCluster. Java would do > > something similar, although the naming convention of the interfaces might > > be different. (In C#, you might even decide to avoid some of the code > > duplication by using extension methods. Or maybe not ... it might cause > > more trouble than it solves.) > > > > Peter > > > > > > _______________________________________________ > > openEHR-technical mailing list > > openEHR-technical at lists.openehr.org > > http://lists.openehr.org/mailman/listinfo/openehr-technical_lists.openehr.org -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openehr.org/pipermail/openehr-technical_lists.openehr.org/attachments/20120323/81bd80ae/attachment.html>
