- From: <jos.deroo.jd@belgium.agfa.com>
- Date: Tue, 18 Jul 2000 12:11:58 +0200
- To: " - *connolly@w3.org" <connolly@w3.org>
- Cc: " - *www-rdf-interest@w3.org" <www-rdf-interest@w3.org>
Dan Connolly wrote: > jos.deroo.jd@belgium.agfa.com wrote: > > I see you making variables and rulesteps URI global. > > I'm not sure I understand what you mean by that. Well, I saw you using #who, #t, #group and also #if1, #if2 #then which are relative URIs I suppose, that's all. > Ah... thanks. I have glanced at that syntax a few > times without understanding. Now I get it. Er... > no, I don't: that's not legal RDF syntax, is it? > the junction propertyNode can only have one child > element, right? I'm also not sure I understand what you mean. The junction is a class name and not a property. Although I see that we get things like literal("var:t") ... hmm ... > > One can use the var namespace to have variable predicates > > which can be useful for higher order logic such as in > > ftp://windsor.agfa.be/outgoing/RCEI/NET/euler/authen.rdf > > I guess this must be possible in shoe-swell as well, > > just wonder how ?-) > > it's pretty straightfoward; see the "transitive" > example in http://www.w3.org/2000/07/hs78/algernon : > > r (x, z) > if > isa(r, transitive-relations) > r(x , y ) > r(y, z) > Is it also possible to have things like r(x, y) if x(y, z) p(z, u) where x stands for an unknown arc? > Recognizing variables by their spelling is one > technique, but it rubs me the wrong way... URIs are > supposed to be opaque (not to mention the illicit > use of an unregistered var: URI scheme). So I model the > fact that a URI is used as a variable in a formula explicitly > using the vars thing (which reduces to a forAll > construct... see the "Relationship to FOPC" > section of .../inference). > I see your point, thank you! > Hmm... I wonder if I can express your model for rules > in terms of the FOPC schema I'm working with... > I think so. I'm really looking forward to that! -- Jos De Roo
Received on Tuesday, 18 July 2000 06:13:11 UTC