Re: Bugs in 2000/12 daml+oil reference on DAML collections

From: Dan Connolly <connolly@w3.org>
Subject: Re: Bugs in 2000/12 daml+oil reference on DAML collections
Date: Fri, 12 Jan 2001 12:46:14 -0600

> No way of typing a list? If you mean that there's no handy
> idiom for it, OK. But there certainly is a way to say
> what we mean; we've said it:
> 
> Ax56.    (<=> (Type ?l Disjoint)
>            (and (Type ?l List)
>*                 (forall (?c) (=> (PropertyValue Item ?c ?l)
>*                                  (Type ?c Class)))
>                 (forall (?c1 ?c2) 
>                         (=> (and (PropertyValue item ?c1 ?l)
>                                  (PropertyValue item ?c2 ?l) 
>                                  (not (= ?c1 ?c2))) 
>                             (PropertyValue disjointWith ?c1 ?c2)))))
> 

This is a mechanism in KIF for typing a list, not a mechanism in DAML+OIL
or in RDF.  (I'm not saying that it is not a good idea to have such an
inference, just that there doesn't appear to be any mechanism for stating
it in RDF or in DAML+OIL.)

Further, the inference marked by * above is not sanctioned by anything in
the DAML+OIL definition, nor in any other DAML+OIL document.

peter

Received on Friday, 12 January 2001 13:58:10 UTC