Punning object and data properties

Some time ago there was a discussion regarding the need (or lack there 
of) punning the same URI for both as an object and a data property. 
Another use case for this is representing arbitrary lists in the 
instance data. The most straight-forward way to represent a list would 
be to use the rdf:List vocabulary where rdf:first can be used both for 
object and literal values. OWL-DL disallows the use of rdf:List 
vocabulary (outside built-in class constructors) and does not have 
punning so the common approach is to recreate the same terms under a 
different namespace and restrict the lists to lists of objects. OWL-S 
shadow list vocabulary [1] is one example and there are other proposals 
for lists with more semantics [2]. Ability to pun object  and data 
properties would generalize this approach to lists of literals. In 
addition, if punning built-in vocabulary (or at least rdf:List 
vocabuary) is allowed it would not be necessary to reinvent a new namespace.


[1] http://www.daml.org/services/owl-s/1.1/generic/ObjectList.owl
[2] Nick Drummond, Alan Rector, Robert Stevens, Georgina Moulton, 
Matthew Horridge, Hai H. Wang, Julian Seidenberg. Putting OWL in Order: 
Patterns for Sequences in OWL. OWLED 2006.

Received on Wednesday, 5 December 2007 05:02:28 UTC