[xquery-talk] XQuery Update Facility and unwanted whitespace

[Michael Kay]

Andrew has answered the whitespace questions.

It's a Saxon (not an Oxygen) restriction that XQuery 3.0 and XQuery 
Update can't currently be used together in the same query. It happened 
that way because both are implemented as extensions to the "core" XQuery 
1.0 parser, built using subclassing. (Done that way partly because of 
the code separation between different Saxon editions). We need to fix 
this mechanism, which is becoming pretty unmanageable with the number of 
different language dialects supported. Ideally, I suppose, we should 
make a complete break and move to a bottom-up table driven parser; but 
XQuery parsing is so fragile with the number of context-dependent 
decisions that need to be made, it's a risky change to contemplate.

Michael Kay
Saxonica

On 09/07/2012 19:45, Joe Wicentowski wrote:
> Hi all,
>
> I'm having a problem with query I wrote that makes use of the XQuery
> Update Facility.  The problem is that unwanted whitespace inserted
> into the results of my query.  Here is my source XML (a TEI-like
> list), the query in question, and the output showing the unwanted
> whitespace:
>
> source.xml:
> -----------------
> <list>
>      <item>See <ref target="#MIDDLEEAST">Middle East</ref></item>
>      <item xml:id="MIDDLEEAST">Middle East <ref target="#d68">68</ref></item>
> </list>
>
> fix-ids.xq:
> --------------
> let $doc := doc('source.xml')
> for $item-id at $count in $doc//item/@xml:id
> let $new-id := concat('in', $count)
> let $new-target := concat('#', $new-id)
> let $targets := $doc//ref[@target = concat('#', $item-id)]/@target
> return
>      (
>      (: fix @xml:ids :)
>      replace value of node $item-id with $new-id
>      ,
>      (: fix @targets :)
>      for $target in $targets
>      return
>          replace value of node $target with $new-target
>      )
>
> output:
> ----------
> <list>
>     <item>See <ref target="#in1">Middle East</ref>
>     </item>
>     <item xml:id="in1">Middle East <ref target="#d68">68</ref>
>     </item>
> </list>
>
> Note that while the query only modifies attribute values, the results
> of the query are somehow re-indented.  (Specifically, in the source,
> there was no whitespace between </ref> and </item>, but in the
> results, </item> is on a new line.
>
> Is this a serialization issue?  Is there a way for me to declare some
> options that will prevent the unwanted whitespace from being inserted?
>
> I'm not sure whether this is a general XQuery issue or an
> implementation-specific issue, so let me know if this isn't the right
> forum for this question.  I'm using oXygen 13 in XQuery Debugger mode
> with Saxon EE-XQuery 9.3.0.5.
>
> (On a related note, I see that XQuery 3.0 has new support for
> serialization options --
> http://www.w3.org/TR/xquery-30/#id-serialization -- but oXygen doesn't
> seem to allow combining XQuery 3.0 with XQuery Update Facility and
> Saxon EE.  This forum post instructs users to disable XQuery 1.1/3.0
> support in order to use XQUF:
> http://www.oxygenxml.com/forum/topic6615.html.)
>
> Thanks,
> Joe
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