Re: [xml-dev] Interoperability

[Joe English <jenglish@flightlab.com>]

Sean McGrath wrote:

> [Joe English]
> >Earlier Sean quoted me as saying that I had given up
> >on DTDs.  I haven't at all; what I *have* given up on
> >is <!DOCTYPE ...> declarations.
>
> Do you mean you use DTDs for validation but you
> don't associate the DTD with the instance via <!DOCTYPE
> or do you mean you don't use DTDs for validation
> but use them for documentation.

The former.  If you point NSGMLS at a suitable catalog
and SGML declaration it can key off the root element type 
name to locate the DTD public text, so I use that for validation.
Other applications don't need the DTD.

The only players that do need it are document authors,
programmers, and validators.  The humans who want it can
be left to their own devices; as for the programs, it
suffices to use a validator that supports OASIS catalogs
and 'FEATURES DOCTYPE IMPLYDEF YES'.

The main drawback to omitting <!DOCTYPE ...> declarations
is that information about the document type has to be
carried out-of-band (e.g., a note saying "the files
in this directory use the TMML vocabulary, see
<URL: http://tmml.sf.net/ >" in a README file).
I suppose using XML namespaces would rectify this, but
that's another barrel of worms.



> I'm not sure I understand and apologies if I have
> misrepresented you.

No need to apologize :-)


--Joe English

  jenglish@flightlab.com