- From: <paul.downey@bt.com>
- Date: Wed, 25 May 2005 13:32:55 +0100
- To: <xmlschema-dev@w3.org>
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@mitre.org] > 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@bt.com [mailto:paul.downey@bt.com] > Sent: Tuesday, May 24, 2005 5:28 PM > To: costello@mitre.org > 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@w3.org > > Yours > Paul > > http://www.w3.org/2005/03/xml-schema-user-cfp > > > > >
Received on Wednesday, 25 May 2005 12:32:59 UTC