- From: Robin Berjon <robin.berjon@expway.fr>
- Date: Mon, 04 Apr 2005 01:32:57 +0200
- To: noah_mendelsohn@us.ibm.com
- Cc: www-tag@w3.org
noah_mendelsohn@us.ibm.com wrote: > Rich Salz writes: >>XML validity is important, and perhaps should be separated from DTD's. > > I have commented a few times on what I take to be one of the great ironies > of XML: The "Extensible" Markup Language is very extensible with respect > to constructs such as attributes and elements, but very inflexible in > (not) allowing for replacement or evolution of its core mechanisms such as > DTDs. And is it not one of the greatest ironies of XML Schema that it failed to learn from that lesson and therefore didn't provide simple and straightforward means to describe extensibility in schemata? I don't disagree with Paul that part of Rich's question can be deflected over to XML Core, but I does seem to me that other parts of it smell like TAG fodder. Within the XML architecture, is it commendable to use DTDs knowing that they do cannot validate namespaced documents? Knowing that all document-oriented languages are built to expect foreign namespaces practically everywhere, is XML Schema built to know enough about extensibility or is it, as some malicious voices would put it, just "ML Schema"? Are we not missing a piece comparable (or equal) to NVDL somewhere? > All > attempts I've seen to inline schemas into the instance wind up with the > schema as part of the element tree, where it doesn't belong. Amusingly, > this means that if the schema is for the whole document, it has to > validate its own existence! Which is a clear demonstration of the limitations in XML Schema that currently prevent document formats that intend to live in an open world to use it. It really shouldn't be that hard to say "I want to validate my namespace, and the others can do whatever it is they want". -- Robin Berjon Research Scientist Expway, http://expway.com/
Received on Sunday, 3 April 2005 23:33:00 UTC