Re: [dita] Support for foreign content vocabularies such as MathMLand SVG

[Christopher Wong <cwong@idiominc.com>]

Erik Hennum wrote:

> Finally, I agree that the <unknown> element doesn't address the 
> attribute extension problem -- an important and difficult problem. The 
> <data> element provides some relief there, though maybe not a complete 
> solution. Anyway, <unknown> would give us the ability to incorporate 
> standard existing vocaublaries for special content -- something that 
> we need, too.
>
I don't think I completely understand your <unknown> proposal. Can its 
content have elements that are NOT specialized from DITA? That is, can 
they have new attributes not defined in DITA? If the answer is no, then 
its utility is doubtful: you cannot include content from arbitrary 
models if their attributes are ruled out. If the answer is yes, then we 
have validation issues. If <unknown> simply means "here be dragons, do 
not parse, do not enter" to a DITA processor, that may not be an issue. 
But if you also want to process the <section> elements in <unknown>, 
then how can that be validated? Remember that many of us still author in 
DTD-based or even barely-XML (FrameMaker) editors.

Chris