Hi Andrew This is not quite correct as we are talking about constraint. The default is what is in the RM. The three states are: 1. As in the RM - no statement 2. Required (optional in RM) 3. Prohibited (optional in RM)
Is that sensible - Sam > -----Original Message----- > From: openehr-technical-bounces at chime.ucl.ac.uk [mailto:openehr- > technical-bounces at chime.ucl.ac.uk] On Behalf Of Andrew Patterson > Sent: Wednesday, 12 May 2010 12:24 PM > To: For openEHR technical discussions > Cc: openehr-technical at openehr.org > Subject: Re: Archetypes and XML-Schemas > > > This is a binary constraint. For this reason we are proposing that > existence > > is represented as an optional attribute with 2 values > > 'required' and 'prohibited'. > > Sam, an optional attribute with 2 values actually allows 3 > states. Of course the default will map to one of the two > values - but this does allow 2 ways of expressing the > same concept. > > My two preferences for this situation (representing > binary constraints) > > a) mandatory attribute with 2 values > > - or - > > b) an optional attribute with ONE possible value, and where > the absence of the value is the default. > > Andrew > _______________________________________________ > openEHR-technical mailing list > openEHR-technical at openehr.org > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical
