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- Date: Thu, 31 May 2007 09:32:09 +0000
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http://www.w3.org/Bugs/Public/show_bug.cgi?id=4551 ------- Comment #3 from tim@cbcl.co.uk 2007-05-31 09:32 ------- I'm now less convinced that ("a string", error()) is of type xs:string. In FS 8.4 quantifier(none) = 1 The type none matches no values, therefore from the FS rules in 8.3.1 Matches and 8.3.2 Subtyping (<:) there is no rule: -------------------------------- statEnv |- error() matches none therefore we can't apply: statEnv |- Value1 matches Type1 statEnv |- Value2 matches Type2 --------------------------------------------- statEnv |- Value1,Value2 matches Type1,Type2 so we have to deduce that whatever type (xs:string, none) is, it certainly isn't a subtype of xs:string. All we can say is that it is of type (xs:string, none), which is roughly xs:string+. Therefore this test should allow for a type checking error as well as the error thrown by error(). Quite a few of the tests use a similar construct, so will also need to permit a type check error. As an aside, I do find it a little strange that (Type|none) = Type _and_ quantifier(none) = 1. It almost seems as if a type which matches no values should have the unusual quantifier of zero.
Received on Thursday, 31 May 2007 09:32:17 UTC