Fw: selecting fragments of xml document that contain certain paths in string variables

[fatma helmy]

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From: fatma helmy <http://x-query.com/mailman/listinfo/talk>
To: http://x-query.com/mailman/listinfo/talk
Sent: Monday, November 6, 2006 3:04:25 AM
Subject: selecting fragments of xml document that contain certain paths in string variables


Dear all
suppose i have this xml books.xml
<root>
<book> 
<author> <firstname>john </firstname> </author>
<price> 10</price>
</book>
<book>
<author> <firstname> mary</firstname> </author>
<price> 100 </price>
</book>
<book>
<price> 100 </price>
</book>
</root>

suppose i have variable $pth:= "book/author/firstname"
i need to restrict the choice to books that contain this $pth

something like that 


let $restrictedxml:= books.xml (containing $pth)