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Oren Ben-Kiki wrote: > > I don't follow. You yourself have said: > > >The IDL for an XML QL should be something like: > > > >NodeList XMLQuery( DOC doc, String query ) > > Well, them, what other way is to return a list of XPointers then to store > each in an "element"? You don't need an element. You just need a nodelist. Look at the DOM's brutally named "getElementsByTagName" method. Also consider the XSL specification: > A select pattern must match the production for SelectExpr; it returns > the list of nodes that results from evaluating the SelectExpr with the > current node as context; the nodes are in the list are in document order. XPointer is interesting because it doesn't support either interpretation: "The result of a spanning selection cannot generally be expressed as a well-formed XML document, nor as a node or list of nodes from an element tree." -- If you are asking me what is the syntax for a nodelist then I'll say it has no syntax. It is an abstraction like the record set returned by a database. If you have to move the query result between machines then you can choose an encoding (quite likely XML) but that's outside of the realm of the query language itself -- it is akin to report writing. If you aren't moving data between processes then you shouldn't be forced to encode it in XML (even a DOM). This is just a general principle that applies here. > This is assuming that you prefer the query engine to > return a list of pointers as a result, which I don't. The one nice thing > about this scheme is that you can add extra data per XPointer - a relevancy > score, for example. I'm not convinced that this is the domain of the query language, but even if it is then you are asking for an annotated nodelist, not a DOM. If we do decide to go ahead with annotated nodelists then we would have to add that to the XML data model. That still doesn't have anything to do with generating XML elements: *unless the application wants to do so*. > I stand corrected. I think you've phrased it perfectly above - the output > should be defined in the terms of the XML data model. And that model has a concept of nodelist -- this is the most appropriate return value for query results. -- Paul Prescod - ISOGEN Consulting Engineer speaking for only himself http://itrc.uwaterloo.ca/~papresco "Perpetually obsolescing and thus losing all data and programs every 10 years (the current pattern) is no way to run an information economy or a civilization." - Stewart Brand, founder of the Whole Earth Catalog http://www.wired.com/news/news/culture/story/10124.html xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev@i... Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/ and on CD-ROM/ISBN 981-02-3594-1 To (un)subscribe, mailto:majordomo@i... the following message; (un)subscribe xml-dev To subscribe to the digests, mailto:majordomo@i... the following message; subscribe xml-dev-digest List coordinator, Henry Rzepa (mailto:rzepa@i...)
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