W3C home > Mailing lists > Public > www-webont-wg@w3.org > September 2002

Fw: DAML-S expressiveness challenge #3

From: Jonathan Borden <jonathan@openhealth.org>
Date: Wed, 11 Sep 2002 23:08:04 -0400
Message-ID: <021501c25a09$9d0919a0$af363418@ne.mediaone.net>
To: <www-webont-wg@w3.org>
Cc: <martin@AI.SRI.COM>

This would be very useful -IMHO

Jonathan

"David Martin" <martin@AI.SRI.COM> wrote:

> 
> Hello rdf-logicians:
> 
> I would like to have a nice way to declare a DAML+OIL property's range
> to indicate that:
> 
> each value of the property is a list, of a particular length,
> and specific list elements must have specific types.
> 
> (What do I mean by "value of a property"?  Siimply this: if <X Prop Y>
> is an instance of property Prop, I call Y a "value of the property".)
> 
> I know how to do this, laboriously and non-readably, using a chain of
> restrictions on "first" and "rest".  But I'm hoping for some syntactic
> sugar.  I am currently using a partially defined property for this
> purpose, called listOfInstancesOf (compare to intersectionOf):
> 
> <daml:Property rdf:ID="listOfInstancesOf">
>   <rdfs:domain rdf:resource="#Class"/>
>   <rdfs:range rdf:resource="#List"/>
>   <rdfs:comment>
>     This is a "place-holder" for now, which needs further work.
>     The range is a list of classes.
>     "Class listOfInstancesOf X Y Z" (for example) is used to indicate
> the class
>     of lists having an instance of class X as their first member, an
> instance
>     of class Y as their second member, and an instance of class Z as
> their
>     third member.
>   </rdfs:comment>
> </daml:Property>
> 
> My question: what is a complete valid definition for listOfInstancesOf
> (if there is one)?
> 
>  Here's a simple example of use (again, compare to intersectionOf) :
> 
>        <daml:Class rdf:ID="MyClass">
>          <listOfInstancesOf rdf:parseType="daml:collection">
>            <daml:Class rdf:about="#LocateBook"/>
>            <daml:Class rdf:about="#CongoBuyBook"/>
>          </listOfInstancesOf>
>        </daml:Class>
> 
> A valid instance of MyClass would be the list of length 2, containing an
> instance of LocateBook as its first element, and an instance of
> CongoBuyBook as its second element.
> 
> Thanks,
> David Martin
> 
> 
Received on Wednesday, 11 September 2002 23:25:16 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:57:52 GMT