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Re: #rdfms-difference-between-ID-and-about

From: Dan Connolly <connolly@w3.org>
Date: Fri, 15 Jun 2001 02:29:02 -0500
Message-ID: <3B29B93E.EE2C9674@w3.org>
To: guha@alpiri.com
CC: Aaron Swartz <aswartz@upclink.com>, Sergey Melnik <melnik@db.stanford.edu>, Brian McBride <bwm@hplb.hpl.hp.com>, rdf core <w3c-rdfcore-wg@w3.org>
"R.V.Guha" wrote:
> 
> Ok, Aaron, you hit the nail on the head.
> 
> RDF absolutely has to make sense even outside the context of
> an enclosing document which can be given a uri. so ...

So... what? That doesn't make any sense to me.

An RDF document is an XML document. Each XML document
has a base URI (cf the infoset spec).
If you copy the contents from one
place in the web to another, you get a different XML
document, and hence a difference RDF document; if
it uses relative URI references, the resulting triples
may be different.

This is by design.

This design does allow users to goof,
but it also allows folks to manage collections of
documents and by and large, it has succeeded over the course
of the last 10 years.

Noone is forced to use relative URI references; anyone
who uses them does so by choice. Surely the consequences
of that choice for RDF documents should be the same
as the consequences for HTML, XML, PDF,
and other document formats in the Web, no?

Or rather: surely the the consequences *are* the same for
RDF as for XML in general; we're not designing RDF 1.0 today;
we're just clarifying the spec; and the spec is already
pretty clear on this:

  [[[ The value of the about attribute is interpreted as
  a URI-reference per Section 4 of [URI]. The corresponding
  resource identifier is obtained by resolving the
  URI-reference to absolute form as specified by [URI].
  ]]]

  --        Resource Description Framework (RDF) Model and Syntax
Specification
  http://www.w3.org/TR/REC-rdf-syntax/
  Wed, 24 Feb 1999 14:45:07 GMT

The only question is about this sort of fuzzy text:

  [[[ The ID attribute signals the creation of a new resource ... ]]]


But this text in particular suggests pretty strongly
that rdf:ID="foo" means the same thing as rdf:about="#foo" :

  [[[ The ID attribute, if specified, provides the URI
  fragment identifier for c. 
  ]]]

  -- section 6. Formal Grammar for RDF

-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Friday, 15 June 2001 03:30:10 EDT

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