- From: C.M.Sperberg-McQueen <cmsmcq@acm.org>
- Date: Mon, 18 Sep 2006 19:35:21 -0600
- To: James Clark <jjc@jclark.com>
- Cc: "C. M. Sperberg-McQueen" <cmsmcq@acm.org>, www-xml-schema-comments@w3.org
James, As XML Schema 1.0 was nearing completion, you filed a comment (archived at http://lists.w3.org/Archives/Public/www-xml-schema-comments/ 2000OctDec/0216) suggesting that it would be convenient to be able to write a wildcard which accepted (say) any element which is both qualified (i.e. has a namespace URI) and not in the XSL namespace. At that time, the Working Group chose not to make any change, and you recorded a "mild dissent" from the group's decision (http://lists.w3.org/Archives/Public/www-xml-schema-comments/ 2001JanMar/0155). Some time has passed, and I don't know whether you still take any interest in the issues you raised then against XML Schema 1.0. But if you do, I hope you will be pleased by the news that the most recent working draft of XML Schema 1.1 has the functionality you described then: a 'notNamespace' attribute and a 'notQName' attribute have been added to the xsd:any element, with the meanings that the wildcard matches names which are not in those namespace, and not in that list of QNames. Fuller details can be found in section 3.10 of the most recent working draft (http://www.w3.org/TR/xmlschema11-1/#Wildcards). In your 'mild dissent', you said My concern is not so much that this particular bit of functionality is missing in 1.0 but rather that you have locked yourself in to a syntactic approach that will make it hard to add it cleanly in the future. Your current design invents an ad hoc non-XML syntax to enable an attribute value to describe a set of namespaces. In general, I would suggest it's a bad approach to try and pack structured information into an attribute value: it often works at first, but as you try to add more features, it runs out of steam and an incresingly baroque and non-orthogonal syntax becomes necessary. I think you would be much better off to use elements in the content of the "any" element to describe the set of namespaces. We cannot claim to have addressed this concern directly; the revised wildcard is syntactically similar to the old one. Whether the revision shows that your concern was misplaced, or justified, I will leave for others to judge. If you still have any interest in this topic, the working group would be grateful to know whether you believe this revision successfully addresses your original issue or not. You will find a record of the issue and our disposition of it in the W3C's public Bugzilla installation, at http://www.w3.org/Bugs/Public/show_bug.cgi?id=2867 and we would be glad if you added a comment to the issue record indicating whether you agree, or do not agree, with our resolution of the issue. Alternatively, you could reply to this email, which I am copying to the public comments list. If we do not hear from you in the next two weeks, we will assume you agree with the WG decision, or have lost interest in XML Schema, if not in all XML schema languages. best regards, Michael Sperberg-McQueen
Received on Tuesday, 19 September 2006 01:36:04 UTC