4134 2007-01-02 18:08:18 +0000 Microsoft "schema" test set, schU1 (circular redefines) 2007-01-11 00:14:29 +0000 1 1 1 Unclassified XML Schema Test Suite Microsoft tests 2006-11-06 PC Windows XP RESOLVED DUPLICATE 4135 P2 normal --- 1 mike ht public-xml-schema-testsuite oldest_to_newest 13324 0 mike 2007-01-02 18:08:18 +0000 In the Microsoft "schema" test set, test <test group="schU1" name="schU1"/> there are two schema documents, each of which redefines the other. The metadata indicates that this is considered valid. I can't find an explicit ban on circular redefines. However, I believe there is an implicit ban. XML Schema Part 1 Schema Representation Constraint: Redefinition Constraints and Semantics states: If the ·actual value· of the schemaLocation [attribute] successfully resolves [then] it resolves to [something which] corresponds to a <schema> element information item in a well-formed information set, which in turn corresponds to a valid schema. In the presence of circular redefines, I don't believe that this rule is decideable. You can't determine whether the information set corresponds to a valid schema without processing the xs:redefines, and this leads to infinite regress. (Perhaps this is wriggling. The same argument could be used to disallow circular xs:include. However, it's relatively easy to find an algorithm for determining that either all the xs:include directives in a cycle are valid, or none of them are. Because of the special semantics of xs:redefine, it's far less clear that such an algorithm exists in this case.) 13430 1 mike 2007-01-11 00:14:29 +0000 *** This bug has been marked as a duplicate of bug 4135 ***