Re: Personal reply to Edd Dumbill's XML Hack Article wrt W3C XML Schema

[Eric van der Vlist <vdv@dyomedea.com>]

Matthew Gertner wrote:
> 
> > I wonder if I have been clear ;=) ...
> >
> > By specifying the data types in the instance, I wasn't thinking to ask
> > the users to type it (except, maybe in very specific cases, but it's
> > already possible using a xsi:type attribute), but rather defining the
> > validation process as a transformation that would add this
> > information's
> > as attributes (or elements).
> 
> Okay, now that I understand what you are talking about, I still disagree,
> but less passionately. :-) Sure, that's a neat idea. We actually use
> something quite similar in our products. The only remaining point of
> contention for me is the statement that data types can vary for the same
> element types for the same instances (i.e. by attaching the instance to
> multiple schemas). This becomes closer to a personally held opinion that a
> universal truth, however. In my view, information architectures based on XML
> will be driven by XML schemas (hence the bean example in my last post). A
> given schema tells you how to process a given class of instances, so you
> have to have a single schema for a given instance. This seems emminently
> logical to me, but I'd be curious to hear some justification for the
> opposite view.

An "official" justification that I have heard from C. M.
Sperberg-McQueen at XML 2000 (I think he was presenting just before you
;=) ) was an example of a B2B application where the guys who are
receiving a document want to apply their own version of a schema that
they do trust and has enhanced controls.

I am no specialist of these types of system and cannot judge if this is
a good case though it seems to make sense.

My own justification is more "guts feeling"...

I think that a great asset of XML is to decouple the documents from the
technology used to process them and I consider W3C XML Schema as a
technology amongst other.

I am as reluctant to create a dependency over W3C XML Schema than I
would be to create a dependency over a specific language or OS.

Of course, if you consider W3C XML Schema as a part of XML 2.0 core, you
will strongly disagree (and find it fine that the other specs rely on
W3C XML Schema).

Eric

> 
> Matt

-- 
Rendez-vous à Paris pour net2001.               http://www.mynet2001.net
------------------------------------------------------------------------
Eric van der Vlist       Dyomedea                    http://dyomedea.com
http://xmlfr.org         http://4xt.org              http://ducotede.com
------------------------------------------------------------------------