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Re: draft partitioning of the issues

From: Aaron Swartz <me@aaronsw.com>
Date: Tue, 26 Jun 2001 11:28:27 -0500
To: Brian McBride <bwm@hplb.hpl.hp.com>
Cc: rdf core <w3c-rdfcore-wg@w3.org>
Message-Id: <20010627014303.JVIT26850.femail19.sdc1.sfba.home.com@localhost>
On Tuesday, June 26, 2001, at 08:33  AM, Brian McBride wrote:

>>> Is there any doubt that as far as m&s is concerned:
>>>   o literals are not allowed as subjects
>>>   o literals are not resources
>> I do not see either of these stated in the spec.
> Yes, I think you are right that it does not state explicitly that they
> are disjoint.  In reading the spec I ascribe some information to the
> fact that m&s calls out that an object can be either a resource or a
> literal and says only that subject is a member of resources.  
> Whilst this
> may not be a mathematically precise statement that resources and
> literals are disjoint, it seems pretty clear that it was the intent
> that they are and that subjects may not therefore be literals.

Really? I've always interpreted this to mean that Literals are a 
subset of resources -- I'm not the only one, TimBL seems to have 

<q cite="http://www.w3.org/2000/10/swap/cwm.py">
class Literal(Thing):
     """ A Literal is a data resource to make it clean

     really, data:application/n3;%22hello%22 == "hello" but who
     wants to store it that way?  Maybe we do... at least in 
theory and maybe
     practice but, for now, we keep them in separate subclases of Thing.

Looking at the code he also seems to store them this way, 
although it's not exactly clear.

> I would agree with you that this could be made more clear.  But I'm
> not sure this is what you are suggesting.

No, I'm suggesting that we make Literals a subset of Resources.

>>> Which is maybe not how some folks would like it to be.  If we
>>> considered introducing this change, do you think we would need 
>>> a syntax change to represent it?  Of course, anyone can now 
>>> use data uri's now if
>>> they want to. We don't have to do anything to support that.
>> No, I do not think a syntax change is necessary. This is simply
>> a change to the abstract syntax.
> Could you give an example of using the current RDF/XML syntax to
> represent a literal as a subject.

Well, it depends on how we define the abstract syntax. I'd 
suggest something like:

<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
<rdf:Description rdf:about="data:text/plain;Chicago">


<data:text/plain;Chicago> <http://rdf.example.org/#startsWith> 
<data:text/plain;C> .

The XML syntax need not change for this.
       "Aaron Swartz"      | ...schoolyard subversion...
  <mailto:me@aaronsw.com>  |  <http://aaronsw.com/school/>
<http://www.aaronsw.com/> | because school makes kids dumb
Received on Tuesday, 26 June 2001 21:43:06 UTC

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