Re: Namespaces, W3C XML Schema (was Re: ANN: SAX FiltersforNamespaceProcessing)

[james anderson <james.anderson@setf.de>]

Ronald Bourret wrote:
> 
> "Fuchs, Matthew" wrote:
> 
> >  Please also note that locally scoped
> > elements are _not_ just elements whose declarations occur in a funny
> > location in a schema. They actually _are_ a different beast from global
> > elements and _must_ be treated as such.  I don't think that the W3C Schema
> > WG ever really came to grip with this fact, given the inadequate support
> > provided for them by spec's component model.
> 
> I think this pretty much sums up the objections to local elements --
> they are a different beast. They don't play well with namespaces and
> they certainly break one of my fundamental assumptions about XML --

what if the element's _definition_ tells you "what" a piece of data is?

this was easy to avoid in a pre-namespaces world. it was harder to avoid
in a post-namespaces world, but people did it any way. it is impossible
to avoid in a psvi-world. in the psvi-world the namespace of the name
and the environment in which the name is resolved to a definition are
simply not the same thing.

> namely that an element's name at least tells you what a piece of data is
> (even if you do need context to determine who that data belongs to).
> This reduces data portability, although the more I think about it,
> complete data portability probably doesn't occur often at the individual
> element level anyway.
> 

given schemas, there's just a different way to locate the definitions.

> ...

> What I can't decide is whether the complexities local element types add
> are worth the benefits they add to serializing object graphs. Put
> another way, I can probably explain element types (as opposed to just
> elements) to my Mom. I don't think I can explain local element types.

in the context of the megabyte of stipulations entailed by xml schema,
context-dependant name->declaration resolution would appear to be a
minor issue.

...