Re: DTD Fragments and XML

Paul Prescod writes:
 > Let's say that I am an XML user. I am happy with, say, the DocBook DTD,
 > but need to insert a chemical formula in CML format. Or perhaps I want
 > to insert something more mundane, some small element that does not have
 > an expression in DocBook: <GRADE> for a student's grade on a project. In
 > the SGML world I would combine the two DTDs manually. This is probably a
 > painful process of examining content models and parameter entities and
 > finding the right place to shoe-horn in my element type. 

Giving up validation just to embed a new document type seems too high
a price to pay. But combining two DTDs into a single one is not
helping anybody either, because even applications that know both DTDs
will probably not be able to handle the combined one. How about this
sub-document:

    <!doctype docbook "http://docbook.org/docbook.spec">
    <docbook>...
    ...
    <!doctype grade "http://grades.org/grades.spec">
    <grade>...</grade>
    ...
    </docbook>

One question: should IDs be local to the sub-document? I think not:
XML-link won't be able to point to an ID in the sub-document unless
the ID is unique in the whole document.


Bert
-- 
  Bert Bos                                ( W 3 C ) http://www.w3.org/
  http://www.w3.org/pub/WWW/People/Bos/                      INRIA/W3C
  bert@w3.org                             2004 Rt des Lucioles / BP 93
  +33 4 93 65 77 71               06902 Sophia Antipolis Cedex, France

Received on Monday, 5 May 1997 08:10:59 UTC