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functx:is-node-among-descendants

Whether an XML node is among the descendants of a sequence, based on node identity

Description

The functx:is-node-among-descendants function returns a boolean value indicating whether or not a node is in the specified sequence, or among the descendants of nodes in a sequence, based on node identity. If $node or $seq is the empty sequence, it returns false.

Nodes are identified based on node identity, not their contents. For a similar function based on the contents of a node, see functx:is-node-among-descendants-deep-equal.

Arguments and Return Type

XQuery Function Declaration

declare namespace functx = "http://www.functx.com";
declare function functx:is-node-among-descendants
  ( $node as node()? ,
    $seq as node()* )  as xs:boolean {

   some $nodeInSeq in $seq/descendant-or-self::*/(.|@*)
   satisfies $nodeInSeq is $node
 } ;

Examples

<prices>
   <price value="29.99" discount="10.00"/>
   <price value="39.99" discount="6.00"/>
   <price value="49.99" discount=""/>
</prices>

<price value="49.99" discount=""/>

functx:is-node-among-descendants(
     $in-xml/price[1],$in-xml)

true

functx:is-node-among-descendants(
     $in-xml,$in-xml/price[1])

false

functx:is-node-among-descendants(
     $in-xml,$in-xml)

true

functx:is-node-among-descendants(
     $aPrice,$in-xml)

false

See Also

History