fyi

-----Original Message-----
From: Downey,PS,Paul,CXMA C 
Sent: 25 May 2005 13:33
To: 'Roger L. Costello'
Subject: RE: W3C Workshop on XML Schema 1.0 User Experiences


Roger,

many thanks, I fully understand that 'swamped' feeling :-)

Just posting this email to the submissions list and allowing
it to be published would be useful for a basis of discussion.
Anything else you could might like to add would be very 
much appreciated.

Best Regards,
Paul

> -----Original Message-----
> From: Roger L. Costello [mailto:costello@m...]
> Sent: 25 May 2005 13:07
> To: Downey,PS,Paul,CXMA C
> Subject: RE: W3C Workshop on XML Schema 1.0 User Experiences
> 
> 
> Hi Paul,
> 
> Thanks.  I have seen the announcements.  I am sure that it 
> would be very
> useful for me to attend.  Unfortunately, I am swamped with work.
> 
> Off the top of my head, I can list five capabilities that are 
> absent in XML
> Schemas which have hampered their use in the programs that I have been
> involved with:
> 
> 1. Co-constraints - the inability of XML Schemas to express 
> co-constraints
> has been a sore point for every program that I have worked.
> 
> 2. Open content - the inability of XML Schemas allow open content has
> resulted in fixed, static schemas, new versions breaking 
> everything, and
> reduced interoperability.  The <any/> element has a limited, 
> useful purpose,
> but it isn't sufficient.  RSS-type extensibility is needed.
> 
> 3. Extending simpleTypes - oftentimes in my programs we have 
> a simpleType
> that contains a bunch of enumeration values.  At a later date 
> we then want
> to be able to extend the simpleType with more enumeration values.
> 
> 4. Unordered sets - the <all> constructor is so constrained as to be
> useless.  In fact, I don't know of any program which uses it 
> due to its
> extreme limitations.  Conversely, there is a tremendous need 
> for expressing
> a set of elements in which ordering is irrelevant.  (So, if 
> it wasn't so
> constrained, it would be used heavily)  
> 
> 5. Non-deterministic content models - disallowing 
> non-deterministic content
> models has forced people to result to unnatural contortions in their
> Schemas.
> 
> I will talk with some people here to see what other things 
> are  important.
> /Roger
> 
> -----Original Message-----
> From: paul.downey@b... [mailto:paul.downey@b...] 
> Sent: Tuesday, May 24, 2005 5:28 PM
> To: costello@m...
> Subject: W3C Workshop on XML Schema 1.0 User Experiences
> 
> Dear Roger,
> 
> I'm writing on behalf of the Program Committee for an up and coming
> W3C Workshop on XML Schema 1.0 User Experiences, and personally
> as a long time admirer of your work on Schema best practices. 
> 
> We wondered if you had seen the calls for participation, and 
> were interested
> in attending? We'd be very interested in your input, even if that was
> limited
> to sending a short 'experience report' which you can still do without
> actually
> attending in person.
> 
> If you have any questions about the workshop, or any comments, feel 
> free to contact me directly, or to the committee via the list:
> xmlschema-dev@w...
> 
> Yours
> Paul
> 
> http://www.w3.org/2005/03/xml-schema-user-cfp
> 
> 
> 
> 
> 

From paul.downey@b... Wed May 25 12:39:30 2005
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