- From: Karsten Tolle <tolle@dbis.informatik.uni-frankfurt.de>
- Date: Tue, 25 Feb 2003 21:20:57 +0100
- To: "pat hayes" <phayes@ai.uwf.edu>, "Graham Klyne" <GK@ninebynine.org>
- Cc: <www-rdf-comments@w3.org>
----- Original Message ----- From: "Graham Klyne" <GK@ninebynine.org> To: "pat hayes" <phayes@ai.uwf.edu> Cc: "Karsten Tolle" <tolle@dbis.informatik.uni-frankfurt.de>; <www-rdf-comments@w3.org> Sent: Tuesday, February 25, 2003 1:53 PM Subject: Re: Clarifications needed for the Collection construct (with CR) > At 05:43 PM 2/21/03 -0600, pat hayes wrote: > >>Would it not make more > >>sense to enter a rdf:Bag instead? But there is also another question: Do we > >>need the collection construct at all? > > > >It was specifically requested by the Webont working group, as a necessary > >requirement for OWL. So the answer is yes. > > I have also found in my own use of RDF that it is sometimes important to > have a collection construct that is "closed"; i.e. to which no new > elements can be added through RDF graph merging. Not having this would > make it impossible (I think) to express certain things without violating > the basic RDF semantics. > > #g > As you can read in my notes (and also in the comments of Pat), that collections per se are not "closed". > At 05:43 PM 2/21/03 -0600, pat hayes wrote: > >>The effect is that by entering a non-blank node someone could enter also > >>to the collection construct elements from outside. This means without > >>any restrictions this construct is not fixed! > > >Right, it is not. Nothing is 'fixed' in this sense in RDF. ... The constructs collection or container are only "closed" or "fixed" when blank nodes are used. Karsten > > ------------------- > Graham Klyne > <GK@NineByNine.org> > >
Received on Wednesday, 26 February 2003 03:16:00 UTC