W3C home > Mailing lists > Public > www-tag@w3.org > January 2003

Re: WebArch Ambiguity about Objects, PLUS Suggested Major Replacement

From: Graham Klyne <GK@NineByNine.org>
Date: Wed, 15 Jan 2003 16:13:23 +0000
Message-Id: <5.1.0.14.2.20030115155415.00a25950@127.0.0.1>
To: Sandro Hawke <sandro@w3.org>
Cc: www-tag@w3.org

At 10:31 AM 1/15/03 -0500, Sandro Hawke wrote:
> > At 12:32 PM 12/30/02 -0500, Sandro Hawke wrote:
> > >      Designers should be careful, however, to distinguish between
> > >      places where a web address is used to directly identify a web
> > >      page and those where it is used in this indirect manner to
> > >      identify something described on the web page.  (This is true
> > >      regardless of the use of fragment identifiers in web addresses;
> > >      they simply involve a portion of a web page.)
> > >
> > >I wonder how much of this statement the TAG agrees with.....   I
> > >wonder how the RDF community would feel about that last paragraph.
> >
> > I, for one, have no disagreement with this final paragraph.  But there's
> > something unsaid, which maybe doesn't need to be said in this context.  In
> > RDF, the referent of a URIref with fragment cannot be assumed to be a part
> > of the referent of the same URI without fragment identifier.  Any such
> > relationship, if it exists, needs to be stated separately.
> >
> > Suppose we have:
> >    someuri:Unicorn
> > and
> >    someuri:Unicorn#leftHindLeg
> > used in some RDF description.  Absent further information, we cannot 
> assume
> > that the second URIref denotes a part of the thing denoted by the first 
> URIref.
>
>I'd certainly agree that the notion of fragment-ness is in the domain
>of web architecture and none of RDF's business.  I like the idea of
>the RDF model theory treating identifiers as completely opaque.
>
>How do you explain to an web expert but newcomer-to-RDF what it means
>to put the string "http://www.w3.org/1999/02/22-rdf-syntax-ns#type" in
>the "Location" or "Address" field of their web browser?

It means to display the view identified by fragment identifier "type" 
within the document retrieved from 
<http://www.w3.org/1999/02/22-rdf-syntax-ns>.

...

Thus:

If the document returned is text/html MIME type, that would be indicated by 
an anchor within the document.

If the document returned is application/xml MIME type, that would be an 
element within the document indicated by the value "type" on an attribute 
of type ID.

If the document returned is application/xml+rdf MIME type, that would be 
the RDF resource indicated by rdf:ID="type", or rdf:about="#type", or 
rdf:about="x", where x is any URI that when made absolute with respect to 
the base URI http://www.w3.org/1999/02/22-rdf-syntax-ns would yield the 
URIref "http://www.w3.org/1999/02/22-rdf-syntax-ns#type".

...

So if the document currently (as of 2003-01-15) obtained from 
http://www.w3.org/1999/02/22-rdf-syntax-ns were returned as 
application/xml+rdf, I would expect to see some rendering of the following 
displayed:
[[
<RDF
   xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
   xmlns:s="http://www.w3.org/2000/01/rdf-schema#">

   ...

   <Property ID="type"
     s:comment="Identifies the Class of a resource" />

   ...

</RDF>
]]

#g


-------------------
Graham Klyne
<GK@NineByNine.org>
Received on Wednesday, 15 January 2003 11:09:27 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 26 April 2012 12:47:15 GMT