1515 2005-06-29 19:35:19 +0000 Contradictory statement: casting to xs:notation permitted/allowed 2005-09-29 11:30:02 +0000 1 1 1 Unclassified XPath / XQuery / XSLT Functions and Operators 1.0 Last Call drafts Other Linux CLOSED FIXED P2 normal --- 1 frans.englich ashok.malhotra public-qt-comments oldest_to_newest 4385 0 frans.englich 2005-06-29 19:35:19 +0000 When reading section "17.1 Casting from primitive types to primitive types" found in the working draft of 4th April,[1] I think contradictory statements can be found. The first statement, which is the second paragraph in the section, reads: "[XML Schema Part 2: Datatypes Second Edition] defines xs:NOTATION as an abstract type. Thus, casting to xs:NOTATION is not permitted." However, when I interpret the "casting table" found a bit below, I judge that xs:NOTATION can be cast to itself(and maybe xs:string). What is correct becomes quickly complicated, in my opinion. I don't see how the situation of casting from xs:NOTATION to xs:NOTATION would occur in practice, since the data type is abstract. Hence, does the table document a casting which is in theory doable but cannot occur in practice? If the "casting table" also included sub-classes of the data types(e.g that casting to/from a xs:NOTATION derivation) it would to me make sense, but I don't see how it does that. Considering that one user(me) is at least confused, the formerly mentioned paragraph could perhaps be deepened a bit. Cheers, Frans 1.http://www.w3.org/TR/2005/WD-xpath-functions-20050404/#casting-from-primitive-to-primitive 4388 1 mike 2005-06-29 22:27:01 +0000 Yes, we probably need to explain this better. Casting to subtypes of xs:NOTATION is allowed, but the standard mechanism of casting across to xs:NOTATION and then down to the subtype doesn't really work here. Michael Kay 4530 2 ashok.malhotra 2005-07-12 21:25:26 +0000 The WGs decided on the joint call on July 12, 2005 to add wording to section 17.1 of the F&O to clarify that casting is not permitted from xs:NOTATION to xs:NOTATION, since it is an abstract type, although it is permitted from one subtype of xs:NOTATION to another. The entry in the table at the intersection of xs:NOTATION and xs:NOTATION should be changed to "M".