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On Fri, 2002-02-01 at 14:08, Jonathan Robie wrote:
> So I believe that XPointer has a right to exist, but I don't think that the 
> full-fledged XPointer should own the fragment identifier. It must be 
> possible to have pointers among documents without implementing all of XPointer.

I believe that's currently possible.

RFC 3023, which defines the XML Media Type, states:
-----------------------------------------
5. Fragment Identifiers

   Section 4.1 of [RFC2396] notes that the semantics of a fragment
   identifier (the part of a URI after a "#") is a property of the data
   resulting from a retrieval action, and that the format and
   interpretation of fragment identifiers is dependent on the media type
   of the retrieval result.

   As of today, no established specifications define identifiers for XML
   media types.  However, a working draft published by W3C, namely "XML
   Pointer Language (XPointer)", attempts to define fragment identifiers
   for text/xml and application/xml.  The current specification for
   XPointer is available at http://www.w3.org/TR/xptr.
------------------------------------------

XPointer doesn't yet own the fragment identifier, and  there is
flexibility on having +xml types register their own fragment identifier
rules as part of the MIME Media Type registration:
------------------------------------------------
   These registrations [+xml] SHOULD also make reference to RFC 3023 in
   specifying magic numbers, fragment identifiers, base URIs, and use of
   the BOM.
-------------------------------------------------

Section 7 does note (as a useful generic processing situation):
--------------------------------------------
o  Fragment identification - XPointers (work in progress) can work
      with any XML document, whatever vocabulary it uses and whether or
      not it uses XPointer for its own fragment identification.
--------------------------------------------

XPointer will, of course, work on any well-formed XML.  That's different
from a requirement that all XML applications must support XPointer.

RFC 3023 is available at:
http://www.ietf.org/rfc/rfc3023.txt

SVG also takes its own approach, well worth further exploration:
http://www.w3.org/TR/SVG/linking.html#LinksIntoSVG

It both subsets XPointer (to IDs and bare names) and provides its own
svgView() scheme, which does very SVG-specific work.
 
Lots to think about.

-- 
Simon St.Laurent
Ring around the content, a pocket full of brackets
Errors, errors, all fall down!
http://simonstl.com


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