Subject: Re: [xsl] What's the difference between xdt:anyAtomicType and xs:anySimpleType? From: Dimitre Novatchev <dnovatchev@xxxxxxxxx> Date: Sun, 3 Jul 2005 09:38:20 +1000 |
> > xdt:anyAtomicType is a true subtype of xs:anySimpleType. > > What derivation/inheritage/type is not a "true subtype"? I used "true subtype" in set theoretic sense as "true subset". A set A is a true subset of a set B if A is a subset of B and there exists an element b belonging to B that does not belongs to A. In the case discussed, xdt:anyAtomicType is a subtype of xs:anySimpleType and there exists a type (such as xs:IDREFS etc.) of xs:anySimpleType that is not a subtype of xdt:anyAtomicType. Cheers, Dimitre Novatchev On 7/3/05, Frans Englich <frans.englich@xxxxxxxxx> wrote: > On Saturday 02 July 2005 23:17, Dimitre Novatchev wrote: > > On 7/3/05, Frans Englich <frans.englich@xxxxxxxxx> wrote: > > > Hi, > > > > > > I wonder, what is the difference between the xdt:anyAtomicType and > > > xs:anySimpleType? It is a type(duh) and hence can code and definitions > > > depend on it, but other than that, does it have any "effective" impact? > > > > > > Why does it exist? If it didn't exist, anySimpleType would have to derive > > > from the imaginary "itemType"; is that the reason? > > > > No. xdt:anyAtomicType is not identical (see below) to xs:anySimpleType. > > > > > Can the anyAtomicType be considered a "marker interface" for atomic > > > values, but that it in practice is an anySimpleType? > > > > Any instance/subtype of xdt:anyAtomicType is an instance/subtype of > > xs:anySimpleType but the reverse is not true. > > Yes, such kind of relationships emerges as soon one have different types. > > > > > > In the XML.com article titled "The XPath 2.0 Data Model"[1] there's a > > > small hint: > > > > > > "The Data Model document adds five new types to the 19 primitive types > > > defined in the Part 2 Recommendation: [...] the xdt:anyAtomicType, an > > > abstract type that plugs a newly-discovered architectural hole [...]" > > > > > > What was the architectural hole(or where can I read about it), and has it > > > any relation to my question? > > > > To represent the set of all types, whose instances are atomic (but not > > list or union) types. > > Yes, good point, missed that. Except for that one(separating it from > union/list types), does there exist any other reason to why anySimpleType > could not be the direct base class of the atomic types? > > > > > > > xdt:anyAtomicType is a true subtype of xs:anySimpleType. > > What derivation/inheritage/type is not a "true subtype"? > > > Cheers, > > Frans
Current Thread |
---|
|
<- Previous | Index | Next -> |
---|---|---|
Re: [xsl] What's the difference bet, Frans Englich | Thread | RE: [xsl] What's the difference bet, Michael Kay |
Re: [xsl] What's the difference bet, Dimitre Novatchev | Date | Re: [xsl] What's the difference bet, Frans Englich |
Month |