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Re: I am he and you are me and we can all ID together

From: Brian McBride <bwm@hplb.hpl.hp.com>
Date: Mon, 16 Apr 2001 17:12:22 +0100
Message-ID: <3ADB19E6.201F6E3A@hplb.hpl.hp.com>
To: Aaron Swartz <aswartz@upclink.com>
CC: RDF Comments <www-rdf-comments@w3.org>
Hi Aaron,

Aaron Swartz wrote:
> 
> The M&S, in section 6, while discussing the abbreviated attribute syntax,
> claims that:
> 
> > 3.    r2 is the resource named by the resource attribute if present or a new
> > resource. If the ID attribute is given it is the identifier of this new
> > resource.
> 
> As Dave Beckett kindly pointed out, this contradicts the previous definition
> of the ID attribute, which was to provide an identifier for the reified
> statement. Thus, the M&S is unclear on the meaning of this attribute, since
> it defines it twice.

I assume Dave is referring to:

  Within propertyElt (production [6.12]), the URI used in a resource
  attribute identifies (after resolution) the resource that is the
object of
  the statement (i.e., the value of this property). The value of the ID
  attribute, if specified, is the identifier for the resource that
represents
  the reification of the statement.

as the contradictory statement. 

> 
> Test case:
> 
> <rdf:Description rdf:about="#x">
>     <a:b rdf:ID="bar" />
> </rdf:Description>
> 
> Additionally:
> 
> <rdf:Description rdf:about="#x" a:c="bar">
>     <a:b rdf:ID="bar" />
> </rdf:Description>
> 
> Since this section specifies treatment of the attribute syntax, some
> interpretations of the spec may believe that these rules are only to be
> followed when the abbreviated syntax is used.

Personally, I have interpretted the spec to mean that ID on a property
element
is treated differently when attribute syntax is used and when element
syntax is
used.  It seemed the only interpretation that worked.  I wonder what the 
different parsers do.

Having ID denote the reified statement in attribute syntax doesn't work
in
general as there may be more than one attribute, thus more than one
statement.
Mind you, this is a problem that the element syntax form has as well,
cf:

  http://www.w3.org/2000/03/rdf-tracking/#rdfms-propElt-id-with-dr

So its my belief that the intent of the spec was to specify different
interpretations for ID in these different circumstances, so I've added a 
reference to this thread under:

  http://www.w3.org/2000/03/rdf-tracking/#rdfms-syntax-desc-clarity

It may be that someone wants to resubmit it as an issue that its wrong
for
ID to be interpreted differently in to very nearly similar
circumstances.

> 
> This may partially be the cause of confusion in
> #rdfms-not-id-and-resource-attr and so may be related. 

Can you explain more clearly how these might be related.

Brian
Received on Monday, 16 April 2001 12:12:14 GMT

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