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- Date: Wed, 11 Feb 2009 17:33:10 +0000
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http://www.w3.org/Bugs/Public/show_bug.cgi?id=4273 zhen hua liu <zhen.liu@oracle.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |zhen.liu@oracle.com --- Comment #31 from zhen hua liu <zhen.liu@oracle.com> 2009-02-11 17:33:10 --- The subtle point here is that the concept of xs:anyType is overloaded with the following 3 distinct meanings: (1) The most general type at the root of the type hierarchy (2) A concrete type during run time to describe node which is not fully schema validated (3) An abstract type during static analysis to describe node which, during run time, might be non-schema validated (xs:untyped) or strictly schema validated (a specific schema type) or not-fully validated (xs:anyType). Therefore, we need to interpret the xs:anyType depending on the context in which it is used. ================================= During static type analysis, we use definition (3), atomization of node of xs:anyType shall be xs:anyAtomicType for element node and xs:anySimpleType for attribute node. Since static type defined by the current formal semantics is pessimistic (any potential run time type error shall be raised), more static type errors shall be raised when one uses xs:anyType. In other words, xs:anyType is NOT nstatic type friendly, users shall either use xs:untyped or specific schema type to describe the node type statically. That is why when SQL/XML standard defines XML type, it allows implementation defined behavior to default XML to XML(xs:anyType) or XML(xs:untyped) so that vendors may choose their friendly default depending on if they implement pessimistic static typing. ======================================= When xs:anyType is used as part of the sequence type syntax http://www.w3.org/TR/xquery/#id-sequencetype-syntax, it uses definition (1). ============================= When reading http://www.w3.org/TR/xquery/#id-typed-value, use definition (2). -- Configure bugmail: http://www.w3.org/Bugs/Public/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the QA contact for the bug.
Received on Wednesday, 11 February 2009 17:33:20 UTC