[xquery-talk] Looping in Xquery- Braces?

[John Snelson]

I think this error depends on the context of the two expressions you've 
given below - which in and of themselves look fine.

In an expression context, you need a comma between two direct element 
constructors:

<a/>, <b/>

When directly inside another direct element constructor, no comma is 
necessary (because the syntax is emulating XML itself):

<root><a/><b/></root>

When you use curly braces inside a direct element constructor, you 
return to an expression context, so commas are necessary again:

<root>{ <a/>, <b/> }</root>

You can mix the two styles:

<root>{ <a/>, <b/> }<c/><d/></root>

John

On 04/09/12 10:58, Mailing Lists Mail wrote:
> Here is what Stumps me about the braces.. Since JOhn's solution worked,
> I wanted to do the same for other element lengths...
> so I did
>
> <short-desc>{
>    sum(
>
>      for $shrtdesc in $ltnfiles//subtopic[@id = 'DEF']//short-definition
>      return string-length($shrtdesc/p/__text)
>    )
> }</short-desc>
>
>
> <long-desc>{
>    sum(
>
>      for $shrtdesc in $ltnfiles//subtopic[@id = 'DEF']//long-definition
>      return string-length($shrtdesc/p/__text)
>    )
> }</long-desc>
>
>
> Ended up getting the following error...
>
>
>         At line 24 column 3:
>
> 22.
> 23. <long-desc>
> 24. {
> 25. sum(
> 26.
>
>
> ANy Ideas please?
>
>
>
>
>
>
> On Tue, Sep 4, 2012 at 10:37 AM, John Snelson
> <john.snelson at marklogic.com <mailto:john.snelson at marklogic.com>> wrote:
>
>     You're close - the missing part is that you want to use the sum()
>     function, ie:
>
>     <short-desc>{
>        sum(
>
>          for $shrtdesc in $ltnfiles//subtopic[@id = 'DEF']//short-definition
>          return string-length($shrtdesc/p/__text)
>        )
>     }</short-desc>
>
>     John
>
>
>     On 04/09/12 10:15, Mailing Lists Mail wrote:
>
>         Dear Xquery Adults,
>
>         I am very new here.. I have some issues with getting my requirements
>         working.. I guess, this should be very simple, but dont seem to
>         get my
>         heads around... THe following is what I want..
>
>         I have loads of XMLs in the Data Store ( markLogic)
>
>         I have to run a query to do the return the string lengths of certain
>         elements from 100 XMLs./
>
>         So my pseudo code will be :
>
>         <results>
>         For all XMLs in the Data store
>         {
>
>              <file filename = "filename of the current file ">
>
>                     <desc> {length of desc at //xx/y/desc }
>               <!--
>              There could be more than one desc, in which case, i would
>         like the
>         sum of all the string lengths of each desc
>         -->
>            </desc>
>
>         <short-desc>
>         {
>              string-length ( //xx//yy/short-desc)
>         }
>
>         </short-desc>
>
>             </file>
>
>         </results>
>
>
>         My attempts:
>
>
>            declare namespace dict =
>         "http://www.lexis-nexis.com/__glp/dict
>         <http://www.lexis-nexis.com/glp/dict>";
>         for $ltnfiles in doc()
>             let $NAME:= document-uri($ltnfiles)
>         return (
>            <ltn  >
>             <name>
>              {$NAME}
>             </name>
>              <short-desc>
>              {string-length(string($__ltnfiles//subtopic[@id =
>         'DEF']/short-definition/p/__text))}
>              </short-desc>
>            </ltn>
>         )
>         THe above works fine, if there is only one short-definition..
>         FOr more
>         than one shortdefiitions, it comes up with the error message
>         obviously
>         because the string does not allow 2 arguments, while the stuff
>         passed
>         into the function is a sequence...
>
>         How do I do another loop inside the first one, for each
>         short-defiitin
>         ... SOmething like :
>
>         for $ltnfiles in doc()
>             let $NAME:= document-uri($ltnfiles)
>         return (
>            <ltn  >
>             <name>
>              {$NAME}
>             </name>
>              {
>              for $shrtdesc in $ltnfiles//subtopic[@id =
>         'DEF']//short-definition
>              <short-desc>
>              {
>              string-length( $shrtdesc/p/text)
>              }
>              </short-desc>
>               }
>            </ltn>
>         )
>            DOEstNT WORK .. :( This wont give me what I want as What I
>         want is a
>         sum (string-lengths of all the short-def) .. But atleast i thought i
>         would get something like
>
>         <short-desc>100</short-desc>
>         <short-desc>344</short-desc>
>
>         ( I would have liked <short-desc>444</short-desc> )
>
>         ANy help would be highly appreciated ..
>
>         Thanks
>
>         Dak.
>
>
>
>
>     --
>     John Snelson, Lead Engineer http://twitter.com/jpcs
>     MarkLogic Corporation http://www.marklogic.com
>     _________________________________________________
>     talk at x-query.com <mailto:talk at x-query.com>
>     http://x-query.com/mailman/__listinfo/talk
>     <http://x-query.com/mailman/listinfo/talk>
>
>


-- 
John Snelson, Lead Engineer                    http://twitter.com/jpcs
MarkLogic Corporation                         http://www.marklogic.com