Re: [xml-dev] The use of XML syntax in XML Query

[Elliotte Rusty Harold <elharo@metalab.unc.edu>]

At 10:46 AM -0500 1/3/02, Jonathan Robie wrote:
>At 10:09 AM 1/3/2002 -0500, Elliotte Rusty Harold wrote:
>>There are two ways to fix this:
>>
>>1. The XSLT solution: Make all XQueries complete, well-formed, XML documents
>
>XQueryX does that. Personally, I'm not sure that XQueryX is 
>something that users would want to write, so it is not the solution 
>to David's problem.
>

I agree, but that's because in large part XQueryX was deliberately 
not designed as a human authorable, human-readable syntax. I think 
XQueryX could be redone in a more user-friendly form if that were 
desired.

>>2. The XPath solution: Make all XQueries look nothing like XML 
>>documents; i.e. no tags, no elements, no attributes
>
>Computed element constructor syntax allows this. Here is Henry's 
>example done in computed element constructor syntax, where the 
>wrapping element is in the XML document, and nothing in the query 
>per se looks like XML:
>
><myQR>
>element bib
>{
>    for $b in document("http://www.bn.com";)/bib/book
>    where $b/publisher = "Addison-Wesley" and $b/@year > 1991
>    return
>      element livre
>      {
>         attribute ann&#xe9;e { $b/@year },
>         element cr&#xe9;ateur { $b/author },
>         $b/title
>      }
>}
></myQR>
>

I haven't seen this before. It does look like a possible solution. 
However, you still need to eliminate the non-computed element 
constructor syntax, which will still cause all the problems of user 
confusion on its own, even if a non-confusing alternative exists.
-- 

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| Elliotte Rusty Harold | elharo@metalab.unc.edu | Writer/Programmer |
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