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At 04:17 PM 12/4/2002 -0500, Norman Walsh wrote: >-----BEGIN PGP SIGNED MESSAGE----- >Hash: SHA1 > >/ John Cowan <jcowan@r...> was heard to say: >[...] >| Again, the mere *provision* of typing metadata does not prevent such reuse. >| However, if *standard tools* assume that the metadata is sound, then >| transgressive reuse may indeed be made difficult. Obviously, purely lexical >| tools are not affected, but tools based on XQuery/XPath2/XSLT2 will not >| be purely lexical in this sense (whereas XPath1/XSLT1 are). > >Taking the specific case of XQuery/XPath2/XSLT2, I'm not sure I see >the problem. Given > ><baz> ><foo n="1">Network Drive</foo> ><bar moo="0902">01803</bar> ></baz> > >I might write a template that matches those elements in a purely >lexical way. > > <xsl:template match="baz">...</xsl:template> I agree with Norm. XQuery is a strongly typed language, but it is designed to allow untyped and typed data to be used together gracefully. In XQuery, you do have to cast if data has a datatype that prohibits a specific kind of operation, but generally not if the data is untyped. The type information available in a query depends greatly on whether schemas have been imported into the query. XQuery can work on well-formed XML, XML governed by DTDs, or XML governed by XML Schema. One query can involve data from all three kinds of XML. I think John Cowan's text implies that there might be problems with reuse if there are datatypes in the data and XQuery is being used to process it. I would be interested in seeing some concrete examples that illustrate this point. Jonathan
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