Re: [PRD] Issues to resolve before publication (examples of Const)

Christian de Sainte Marie wrote:
> Gary Hallmark wrote:
>>
>> jim:today is not a valid xml serialization.
>
> Supposing that Jim's namespace is http://rif.examples.com/2008/jim#, 
> would the following be correct?
>
> <Const type="rif:iri">
>    http://rif.examples.com/2008/jim#today
> </Const>
>
yes
>>> As a consequence, I also removed the example 2.1.e (but I would still
>>> like to understand your comment in [3], Gary).
>>
>> my point is that we don't have any support for user-defined datatypes 
>> and it's not necessary for the example, so it should be removed.
>
> Yes, I got that much (and I removed the example). When I wrote that "I 
> would still like to understand your comment, I was refering to the 
> second part of it (from "Maybe we need..."):
just a musing that one can express much of one's datamodel in BLD/FLD, 
and maybe instead of trying to invent a datamodel for PRD one can embed 
rules about one's datamodel.  This would give rise to a PRD ruleset that 
contains
BLD/FLD rules to convey datamodel constraints.  E.g. a rule to say that 
the empno
for an Emp is unique:

?x = ?y :- ?emp#Emp and ?emp[empno->$x empno->$y]

The following 2 rules could be used to define a DayOfWeek

DayOfWeek##xs:string
?d = "Monday" or ?d = "Tuesday" or ... :- ?d#DayOfWeek