RE: [dita] foreign element description issue (non-XML?)

["Grosso, Paul" <pgrosso@ptc.com>]

> -----Original Message-----
> From: Rodolfo M. Raya [mailto:rmraya@maxprograms.com]
> Sent: Monday, 2009 December 28 10:11
> To: 'dita'
> Subject: RE: [dita] foreign element description issue (non-XML?)
> 
> > -----Original Message-----
> > From: Kristen James Eberlein [mailto:kris@eberleinconsulting.com]
> > Sent: Monday, December 28, 2009 1:40 PM
> > To: dita
> > Subject: Re: [dita] foreign element description issue (non-XML?)
> >
> > How about the following wording:
> >
> > The <foreign> element allows the introduction of non-DITA content,
> for
> > example, MathML, SVG, or Rich Text Format (RTF). If the <foreign>
> > element contains more than one type of non-DITA content, processors
> > /should/ render all the content types. Specialization of the
> <foreign>
> > element generally is implemented as a domain, but architects looking
> > for more control over the content can implement foreign vocabularies
> as
> > structural specializations.
> 
> 
> Hi,
> 
> That's not clear enough.  Anything that you add to a DITA file must
> preserve the validity of the file.

That's a general truth, not something we need to discuss under
the description of the <foreign> element.

> 
> If you add non-DITA XML markup, you must do so using namespaces and the
> namespace must be declared in the file. Otherwise, the DITA file
> becomes invalid from XML point of view.

One can use the <foreign> element without namespaces if one
is inserting something like RTF because there are no elements.

And the <foreign> element description does have an example showing
SVG and MathML (and proper declaration of namespaces), so I don't
think we need to get into such details here.  (And we didn't get
into such details in earlier drafts.)

> Notice that, you cannot declare
> a standard DTD in your DITA file, you have to use an XML Schema
> instead.

That's not true.  The content model of <foreign> is ANY which 
allows any element (as long as it is declared in the DTD).  One
does not have to use XSDs.

> 
> Also, in order to use elements from a foreign namespace, DITA schemas
> have to provide the necessary extension points. If the official schemas
> don't allow foreign elements inside <foreign>, then the content model
> is restricted to text, CDATA sections, XML comments and XML Processing
> Instruction.

That's not true.

The content model of <foreign> is ANY, so any (declared) element is
allowed within <foreign>.

I think Kris' latest wording is fine.

paul