Michael Kay is the developer of the Saxon XSLT/XQuery/XMLSchema processor, a member of the W3C XSL, XQuery, and Schema Working Groups, and the author of XSLT 2.0 Programmer’s Reference
XML Schema is in an odd position: everyone is using it, but no-one really likes it. It's clearly fit for purpose, or people wouldn't be using it; but it attracts complaints both because of its immense complexity and because there are basic features that it doesn't provide. Version 1.1 in on the way: this talk surveys the new features and tries to assess whether they will solve the problem.
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