Therefore, we can increase the "type safety" of the XSD by restricting the category of child elements that can be placed in the class element. However, I don't know how to do this in XSD - any pointers?

Assuming you know all the possible elements up front, this is done with a <xs:choice> and/or <xs:sequence>. However, I suspect what you are saying is that there could be elements that aren't known at the time the XSD is generated.

-Dan

--
Dan Allen
Senior Software Engineer, Red Hat | Author of Seam in Action

http://mojavelinux.com
http://mojavelinux.com/seaminaction

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