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RE: Legal Persons

From: John McClure <jmcclure@hypergrove.com>
Date: Tue, 28 Aug 2007 10:50:33 -0700
To: "Turner, David" <davidt@hp.com>, "Owl Dev" <public-owl-dev@w3.org>
Message-ID: <MGEEIEEKKOMOLNHJAHMKGENEEFAA.jmcclure@hypergrove.com>

>> I'm not sure what the reasoner would do with the <rdf:Alt>

Thanks for taking this matter up. Your answer clarified important distinctions
between lists and containers.

What I'm reminded by this exchange is that rdfs:range is a specification of an
extent - rdf:Class is therefore the range of the range property. Accordingly the
<unionOf> property should be used to describe the class whose extent is the
range.  The <unionOf> property identifies an extent formed by a list of one or
more classes -- rdf:List is therefore the range of <unionOf>. The
parseType='Collection' is merely a signal for the construction of an rdf:List,
as Dan Connolly demonstrated (although the tool should generate <rdf:List>s
rather than untyped <rdf:Description>s) and is thus merely syntactic sugar.

So it was totally incorrect to use rdf:Alt, a subclass of rdfs:Container, as the
predicate object, An rdfs:Container graph is quite different from an rdf:List --
with <li> properties not <first> and <next> properties, plus others.  My mistake
came from confusion between Collection & Container -- I had remembered that
"Collection" was the superclass for rdf:Alt and had surmised a connection
between the two when actually none exists (except for a common superclass).

Wouldn't it have been much clearer to have parseType='List' ? Both lists and
containers are collections. So now I must ask: if there is a property whose
range is rdf:Container, do reasoners generate the proper Container graph if
parseType='Collection' ? IOW, is the parseType syntactic sugar for specifying
the memberships of both lists AND containers? If not, why not?

John McClure
Received on Tuesday, 28 August 2007 17:49:58 UTC

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