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Unanswered Questions

From: Ian Stokes-Rees <ijs@decisionsoft.com>
Date: Thu, 10 May 2001 15:49:21 +0100
Message-ID: <3AFAAA71.E759FB7@decisionsoft.com>
To: "xmlschema-dev@w3.org" <xmlschema-dev@w3.org>
Over the last few weeks I have posted a number of questions which have
gone unanswered.  In hopes that the knowledgable people in this area
might be back from Holidays after their completion of the XSDL
Recommendation, I was hoping I could get some feedback.

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> > Assertion #4: One schema document may define a subset of at most one
> > namespace. (that subset may be the entire namespace, or may be no
> > namespace, in the case of "null namespace" schema documents).
> 
> Yes, although your choice of words is odd.  A schema only addresses
> the syntax of elements and attributes in a namespace, there are lots
> of other things that might be defined about a namespace.

I have been reflecting on this comment with respect to the
"form" attribute.  Is it true that anything with
form="unqualified" (whether from an explicit form attribute or
inherrited from the xxxxxFormDefault attribute on the schema element)
is
being defined into the null namespace rather than into the target
namespace of the schema?

If this is the case, then is it correct to say that a single schema
document may define elements and attributes into the null namespace,
the
target namespace of the schema document, or both?

Finally, for globally declared elements and attributes there is no
concept
of "form" since they can only be defined into the target namespace,
although that target namespace may be the null namespace.  Similarly,
globally declared types and groups can only ever be defined into the
target namespace.

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The Primer seems to suggest that fractionDigits is an acceptable facet
for
many integer derived data types.  The SforS and Part 2: Datatypes
support
the conventional wisdom that integer style numbers can't have a
fractional
part.

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Is it legal XSDL to define an infinitely recursive structure?  For
example (in XSDL shorthand):

<element name="foo" type="bar" />
<complexType name="bar">
  <element name="foo" type="bar" minOccurs="1" maxOccurs="1"/>
</complexType>

I can imagine this would be fine if minOccurs="0" because it could
conceivably terminate, however with minOccurs="1" an instance document
with a "foo" element in it would be infinite and impossible to
generate.

************************************************************************


-- 
Ian Stokes-Rees                       DecisionSoft Ltd.
Telephone: +44-1865-203192            http://www.decisionsoft.com
Received on Thursday, 10 May 2001 10:49:13 GMT

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