Gavin,
>
> I think the term "type" here is often interpreted to mean "type" in
> the sense of "int", "float" etc. as found in strongly typed computer
> programming languages. Perhaps for SGML, which required DTD's , and so
> to a degree was statically typed (hah!) it was similar, but I think
> for XML, the notion of "type" is really much looser.... very much
> closer to the Common Lisp way, where type is by projection, as Joe
> pointed out. In practise, this was usually true of SGML too...
Ok. I think I agree.
>
> > I am not sure what you mean. I am saying that I find it useful from
> > a processing POV, to consider an element's name, just as what XML
> > 1.0 says, its "type" and moreover that this defines the "isa" link.
>
> Sure. I think many people find this useful. My point is that the
> 'is-a" is not intrinsic... though the XML specification's use of the
> word 'type' might lead you to believe so. The application decides how
> 'is-a' relationships are decided.
>
> > What is the myth? "isa" links have been used forever. A "name" is a
> > character string, right, what is open to interpretation?
>
> I should have been more precise, sorry. When I say "isa is a myth", I
> meant "isa links are intrinsic is a myth". Again, my assertion is
> that 'is-a' only exists in the context of a given interpreter.
Yes I largely agree. You could define your "isa" link to be based on the
value of an arbitrary attribute, I guess this is what AF does, for example.
>
> > At the end of the day, we do all this because it is useful, and the
> > utility of thinking about namespaces in one way or another is purely
> > the usefulness of doing so.
>
> Sure, in the context of a given application, one style is preferrable
> to another mostly because of it's utility.
>
At the end of the day what is important is that we either have private
agreements or agreed upon conventions for how document is processed, even
from a syntactic point of view. So what AF might do, to give another
example, might be to return the value of an arbitrary attribute as the name
of the element, etc.
Jonathan
