Re: [xsl] Question regarding namespaces

[Chris von See <chris@xxxxxxxxxxxxx>]

On Apr 8, 2008, at 1:57 AM, Michael Kay wrote:

> > I have a stylesheet which I use to normalize various versions of a
> > DTD.  Some old XML documents created against this DTD do
> > not include a default namespace declaration on the root element  
> > but the
> > newer ones do, and I think the way I have to handle this is to have
> > two templates in my stylesheet, one of which selects root elements  
> > without
> a
> > namespace and one which does:
>
> Since the default namespace declaration changes the namespace of every
> element in the document, not just the root element, my preferred  
> approach to
> this kind of problem is to write your stylesheet to handle the case  
> with a
> namespace, and then insert an extra stage into your processing  
> pipeline to
> add the namespace for the older documents that don't have it. This  
> keeps
> things much more simple and modular, and allows you to throw away the
> non-namespace code when the problem is resolved at source.

That's essentially what my "normalizer" does.  The stylesheet in  
question is a preprocessor which restructures the older documents -  
adds the namespace, addresses DTD differences between versions, etc.  
- and makes them valid against the current DTD prior to the main  
processing in a different stylesheet which is linked to the  
normalizer via JAXP.  The template that processes older document  
roots directs processing of the older child nodes by using templates  
with modes, while newer documents are passed through essentially  
unchanged.  I did it this way so that I could run the normalizer  
against any document regardless of its age, since determining the  
vintage up front requires opening the document in some mode (unparsed  
text or XML) anyway.

Cheers
Chris