[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: Re: determining ID-ness in XML

• From: David Brownell <david-b@p...>
• To: veillard@r...
• Date: Thu, 01 Nov 2001 12:19:11 -0800

>       If the IDness
> of attributes is defined in a DTD then having the instance define this
> property too open wide the door to an array of problems due to the
> conflicts between the DTD and the instance:

Hence my initial enthusiasm for an xml:id-ish solution, if one could
be found that didn't mandate only one ID per element.  (There can be
many reasons to label a node; one-label-per-node restrictions are
trouble when labels get very much use.)  Maybe "xml:ids".


>   It may take quite a bit of time before finding and making decisions
> for all the corner cases associated to an indirect IDness mechanism.

Where the indirection was the "list the ID attributes in the instance"
(the xml:idatts approach) ... a related issue is that such mechanisms
are error prone.  They can work, if everyone agrees.


> If people don't want to do validation, then xml:id should be used, but
> if the document was authored with a DTD in mind, using an indirection
> mechanism to try to bypass the author intent doesn't seems to me to be
> an improvement, quite the opposite. 

I think that's mixing several things up.  "Wanting to do validation" is a
policy issue, unrelated to author intent, just like "wanting to avoid
reading the external subset".  Having a DTD is orthogonal to those,
and is more akin to author intent -- but isn't the same as wanting
to identify particular nodes by name/role (rather than the less stable
notion of "position" or, as Len said, "address").

I think the problem is needing stable node identifiers (by name/role)
that don't force document authors to declare them in internal subsets
(or use Schema-du-jour) to ensure that minimally conformant XML
parsers will see the decls.  So the question becomes where they get
identified.  A "global" definition, like an "xml:ids" attribute, seems to
be the least invasive/error-prone solution yet proposed.

- Dave

• References:
  • Re: Re: determining ID-ness in XML
    • From: Jonathan Borden <jborden@m...>
  • Re: Re: determining ID-ness in XML
    • From: Daniel Veillard <veillard@r...>

• Prev by Date: Re: Re: determining ID-ness in XML
• Next by Date: RE: XML Database Decision Tree?
• Previous by thread: Re: Re: determining ID-ness in XML
• Next by thread: Re: Re: determining ID-ness in XML
• Index(es):
  • Date
  • Thread