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At 10:42 AM 12/5/2002 -0700, Uche Ogbuji wrote:
>1) From my last reading of XPath 2.0, schema "import" was not optional if the
>document had a PSVI. If this has changed, this is a big step forward.
It has always been optional, whether or not the document has been schema
validated. (Of course, XQuery operates on the Data Model, not the PSVI).
>2) Even if schema import is optional, it is all or nothing. More likely, I
>want to use type information in, say, one template, and not across the board
>for all values.
This has never been true - XQuery has always allowed you to import just the
schemas for which you want type information.
> > Building data types into the schema doesn't seem harmful. That's the
> > point of a schema, is it not?
>My point is that it ensures tight coupling.
I can do queries on data without importing the schemas into a query, and
the built-in data types in instances are available whether or not I import
schemas into a query.
It would be very helpful for me if you could explain just exactly what you
mean by tight coupling.
> > | which means they now affect all XPath, XSLT and XQuery operations on
> > | This, I think is where the brittleness emerges.
> > Sometimes I write stylesheets that are entirely data type agnostic,
> > but not really very often. I don't see how building data typing into a
> > particular stylesheet or query is harmful.
>I didn't say building it into a particular stylesheet or query is harmful. I
>said that if the data typing info in the PSVI is used at the basic XPath
>processing info, that this is harmful, except in skilful hands.
Can you give me some examples of what you fear?
> > | * The lack of modularity in W3C efforts to incorporate data typing
> into XML
> > | technologies
> > Do you mean because they're tied more-or-less exclusively to WXS? Or
> > do you mean something else?
>Bound to PSVI, to be specific. And I also mean that there hasn't been enough
>work in defining profiles that define generic processing (including
>constraints processing) for those who don't want static typing.
Static typing is optional. Schema import is optional. Is this what you are