Re: ANN: SAX Filters for Namespace Processing

[Ronald Bourret <rpbourret@rpbourret.com>]

"David E. Cleary" wrote:

> Let's take this argument to an extreme. There are members of the XML
> community who loudly argue that using attributes is a bad practice. XML
> Schema could have taken this point of view and not created attribute
> declarations. ... XML Schema had to be able to model as much
> of well formed XML as possible.

I finally understand your point here. It's interesting, because I had
always thought of XML Schemas as a way to build document models.
Modeling well-formed XML was obviously a requirement that had to be
fulfilled, but more of one that sat in the background. The reason for
this was that some well-formed documents just aren't worth modeling,
even if it should be possible. XSLT style sheets are a good example of
this, since you generally would need one DTD per stylesheet.

My point was not that XML Schemas shouldn't be able to model any
well-formed XML -- it should, and doing something like omitting
attribute definitions would break this. My point was that by including a
convenience feature -- which I believe local element types and
elementFormDefault are -- you effectively legitimize the practice that
the feature supports.

-- Ron

P.S. For extra credit, I have three questions:

1) Is there any well-formed XML that a DTD can't model? I can't think of
any (namespace issues aside).

2) Is there any well-formed XML that XML Schemas can't model? Again, I
can't think of any.

3) Are local element types and the elementFormDefault attribute
necessary to model well-formed XML? Again, I'm pretty sure that the
answer is no.