Re: Namespaces, schemas, Simon's filters.

[Richard Tobin <richard@cogsci.ed.ac.uk>]

>OK, I think I get it.  Local element types allow the <line>
>element to have different validation rules depending on 
>whether it's a child of <matt:music>, <matt:graphics> or 
><matt:text>.  Clearly something that DTD's can't do but is 
>desirable.

>I have a question.  With schemas, can I arrange for the
><matt:line> (note it's in a namespace) element to be validated 
>differently depending on whether it's a child of <matt:music>, 
><matt:graphics> or <matt:text>?  -Tim

Yes, these are exactly the two cases we're arguing about.  A local
element declaration inside the type of matt:music

  <element name="line" form="unqualified"> ...

locally declares the element line (in no namespace), whereas

  <element name="line" form="qualified"> ...

locally declares the element matt:line.  The default value for "form"
can be set with the elementFormDefault attribute, and the default
default is unqualified.  The same goes for attributes, where (in my
opinion) unqualified is a lot more natural.

There are two points in dispute: whether local elements are good at
all, and whether unqualified ones are (no doubt there is also a view
that *only* unqualified ones are good, but I haven't noticed anyone
arguing that).

-- Richard