W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > November 2002

Re: Feedback request

From: Brian McBride <bwm@hplb.hpl.hp.com>
Date: Fri, 01 Nov 2002 09:44:28 +0000
Message-Id: <5.1.0.14.0.20021101092525.034f4a08@0-mail-1.hpl.hp.com>
To: pat hayes <phayes@ai.uwf.edu>, w3c-rdfcore-wg@w3.org, dan Brickley <danbri@w3.org>

At 21:28 31/10/2002 -0600, pat hayes wrote:

>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 .

Oh dear, I knew this would come up sometime.  This will get into the are 
resources literals issue and pretty much allows literals as subjects:

   aaa ppp "10" .
   aaa ppp _:l .
   _:l rdfs:type rdf:Literal .

Blank nodes come from anonymous resources and a lot of folks, not all, read 
M&S as Frank did that literals and resources are disjoint.  I'd rather we 
stayed away from these, but I suspect its too late in that we have test 
cases of this form, e.g. the tidy entailment.


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

Ha!


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

I'm tempted not here as it gives us vocabularly to talk about the old style 
literals.  Folks who wrote

   aaa rdfs:range rdf:Literal .

won't suddenly find that integers are now allowed as property 
values.  There again maybe they would want that.

This is the sort of question where I'd want to hear Danbri's judgement as 
he has a good feel for how such changes might go down in various sections 
of the community.


>------
>
>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?)

Broken containers?  Leaky containers?


I've been using the forms:

   Containers for the old style containers
   Collections (based on the parseType term) for lists and explaining that 
a collection is represented as a list structure.

But I'm not wedded to it.  I do need to know by next Thursday though, a 
deadline for something else I'm writing.


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

rdf:Literal


>------
>
>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??

My understanding is we took this out when we simplified datatyping back in 
the summer.  I think the deal is that WE are not standardizing this but a 
future WG likely will, so we don't do it now, but we also don't do anything 
that would break it.


>------
>
>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
>
>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
>
>-----
>
>Thanks.
>
>Pat
>
>
>--
>---------------------------------------------------------------------
>IHMC                                    (850)434 8903   home
>40 South Alcaniz St.                    (850)202 4416   office
>Pensacola                                       (850)202 4440   fax
>FL 32501                                        (850)291 0667    cell
>phayes@ai.uwf.edu                 http://www.coginst.uwf.edu/~phayes
>s.pam@ai.uwf.edu   for spam
Received on Friday, 1 November 2002 04:41:55 EST

This archive was generated by hypermail pre-2.1.9 : Wednesday, 3 September 2003 09:53:55 EDT