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Re: Feedback request

From: Dave Beckett <dave.beckett@bristol.ac.uk>
Date: Fri, 01 Nov 2002 12:47:45 +0000
To: pat hayes <phayes@ai.uwf.edu>
cc: w3c-rdfcore-wg@w3.org
Message-ID: <5652.1036154865@hoth.ilrt.bris.ac.uk>

>>>pat hayes said:
> 
> Quick request(s) for feedback. There are 5 parts to this message.
> 
> Please say if you think that any of the following entailments should 
> NOT be valid in RDF or RDFS, or have any problems with the reasoning 
> sketched. Obviously "10" can be any string.
> 
> 1. (RDF)
> aaa ppp "10" .
> -->
> aaa ppp _:xxx .
> 
> 2. (RDF)
> aaa ppp "10"^^datatypefoo .
> -->
> aaa ppp _:xxx .
> 
> 3. (RDF)
> aaa ppp "10"@lang .
> -->
> aaa ppp _:xxx .
> 
>  From the above, and assuming bare literals denote themselves, then IR 
> must contain all bare literals (cuzof 1) and all values that any 
> datatype can map them into (cuzof 2) and maybe all pairs of all those 
> things with lang tags (not yet sure about that last one). So we might 
> as well say that IR contains all of LV, seems to me. In which case we 
> would get

OK with me.  My feeling is "10", "10"^^datatypefoo, "10"@lang and all
variants are just literal blank boxes as far as the formal semantics
are concerned - you don't/can't look inside.  Ditto for URI-refs.


> 4. (RDFS)
> rdfs:Literal rdfs:subClassOf rdf:Resource .

We've not made that decision yet; left it undetermined.
I can concur with this

> 5. (RDFS)
> aaa rdf:type rdfs:Datatype .
> --->
> aaa rdfs:subClassOf rdfs:Literal .

No idea.

> ------
> 
> Terminology question: now we have lists, should the term 'container' 
> be understood to include lists as well as seqs, bags and alts? If so, 
> does anyone have an suggestion for a generic term for the older 
> containers? (Simple containers? Open containers? Bushy containers?)
> 
> ------

I'm sure we are going to get people confused with collections and
containers.  Since we decided not to create a new way to do seqs,
bags, alts (ha ha!), we should try to be as distinctive as possible.

I think the new things should have the longer name.  I've been using
closed collections but that doesn't seem to have grabbed people much.


> Can anyone fill in the blank for
> 
> rdfs:comment rdfs:range ??? .

I'd leave that out completely.

> ------
> 
> Er..sorry, I ought to know this, but I am honestly unable to recall 
> where the hell we are now. Have we decided to NOT allow property 
> datatyping, ie the use of a datatype URI as a property to link a node 
> to a bare literal, with the datatype implication that the node 
> denotes the resulting value? Or to ALLOW it? That is, should
> 
> 6.
> aaa ppp "10"^^datatypefoo .
> --->
> aaa ppp _:xxx .
> _:xxx datatypefoo "10"
> 
> or not? If so, how about the reverse entailment??
> 
> ------
> 
> Finally, here is my current take on the total RDF and RDFS 
> namespaces. Please correct any errors or omissions. In particular, 
> did we trash rdf:containerMembershipProperty?
> 
> RDF:
> rdf:type   rdf:Property
> rdf:Statement rdf:subject rdf:predicate rdf:object
> rdf:Seq rdf:Bag rdf:Alt rdf:_1 rdf:_2 ...
> rdf:List rdf:first rdf:rest rdf:nil

Checking
  http://ilrt.org/discovery/2001/07/rdf-syntax-grammar/#section-Namespace 
you missed rdf:value which is rdf:type rdfs:Property but has no other
special semantics, as I recall.

> RDFS:
> rdfs:domain rdfs:range rdfs:Resource rdfs:Literal rdfs:Class 
> rdfs:subClassOf rdfs:subPropertyOf rdfs:member rdfs:Datatype
> rdfs:seeAlso, rdfs:isDefinedBy, rdfs:comment  rdfs:label

Seems fine.

Dave
Received on Friday, 1 November 2002 07:49:52 EST

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