Multiple namespaces

People often talk as if namespaces mix with each other randomly.
Actually, more often namespaces have specific extensibility features
that could be thought of as places where you can plug in another
namespace.

So my XSLT document type is probably "XSLT with XHTML output
vocabulary". Similarly, you could imagine a document type of "XML Schema
with XHTML documentation, WSDL and .NET My Services Appinfo and MyNS
target vocabulary".

These extension roles of a namespace could be defined in its RDDL or
schema or both.

I think that it will eventually be possible to assemble, precise,
concise, clear document type statements for multi-namespace documents
just as we did in the "good old days" of SGML where there was always a
single namespace. 

Clarifying extension points is also important for building robust
software. XHTML processors will see foreign data and typically not know
what to do with it. XML Schema, XSLT and WSDL (as a few examples) have
more clear extension rules and extension roles so that they know whether
the unknown data is trying to act as documentation or as metadata or as
the target namespace.

 Paul Prescod

Received on Tuesday, 15 January 2002 18:44:35 UTC