I am assuming you want to solve this problem using XSLT 1.0. I have
used the nodeset extension function in my solution below.

paths.xml
--------------

<Paths>
 <path1>books.book.author.name</path1>
 <path2>books.book.name</path2>
</Paths>

input.xml
-------------

<books>
 <book>
   <name>a1</name>
   <price>10</price>
   <author>
     <name>b1</name>
     <gender>m</gender>
   </author>
 </book>
 <book>
   <name>a2</name>
   <price>10</price>
   <author>
     <name>b2</name>
     <gender>f</gender>
   </author>
 </book>
</books>

test.xsl
-----------

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                      xmlns:xalan="http://xml.apache.org/xalan"
                      version="1.0">

 <!-- iterate over all child elements -->
 <xsl:for-each select="*">
   <!-- strore path in a variable -->
   <xsl:variable name="path1">
     <xsl:call-template name="ConstructPath1">
       <xsl:with-param name="x" select="." />
       <xsl:with-param name="result" select="''" />
     </xsl:call-template>
   </xsl:variable>

   <!-- accumulate output -->
   <xsl:variable name="rtf">
     <xsl:for-each select="$doc2//*">
       <!-- strore path in a variable -->
       <xsl:variable name="path2">
         <xsl:call-template name="ConstructPath2">
           <xsl:with-param name="x" select="." />
           <xsl:with-param name="result" select="''" />
         </xsl:call-template>
       </xsl:variable>

       <!-- compare paths -->
       <xsl:if test="$path1 = $path2">
         <dummy><xsl:value-of select="$path1" /></dummy>
       </xsl:if>
     </xsl:for-each>
   </xsl:variable>

   <!-- eliminate duplicates from accumulated output; and print result -->
   <xsl:for-each select="xalan:nodeset($rtf)/dummy[not(. =
preceding-sibling::*)]">
     <xsl:value-of select="." /> : exists <xsl:text>&#xa;</xsl:text>
   </xsl:for-each>
 </xsl:for-each>
</xsl:template>

<!-- construct path, given a string of form x.y.z -->
<xsl:template name="ConstructPath1">
 <xsl:param name="x" />
 <xsl:param name="result" />

 <xsl:choose>
   <xsl:when test="contains($x, '.')">
     <xsl:call-template name="ConstructPath1">
       <xsl:with-param name="x" select="substring-after($x, '.')" />
       <xsl:with-param name="result" select="concat($result, '/',
substring-before($x, '.'))" />
     </xsl:call-template>
   </xsl:when>
   <xsl:otherwise>
     <xsl:choose>
       <xsl:when test="string-length($x) &gt; 0">
         <xsl:value-of select="concat($result, '/', $x)" />
       </xsl:when>
       <xsl:otherwise>
         <xsl:value-of select="$result" />
       </xsl:otherwise>
     </xsl:choose>
   </xsl:otherwise>
 </xsl:choose>
</xsl:template>

<!-- construct element path, given an element node as input -->
<xsl:template name="ConstructPath2">
 <xsl:param name="x" />
 <xsl:param name="result" />

 <xsl:choose>
   <xsl:when test="$x/..">
     <xsl:call-template name="ConstructPath2">
       <xsl:with-param name="x" select="$x/.." />
       <xsl:with-param name="result" select="concat('/',
local-name($x), $result)" />
     </xsl:call-template>
   </xsl:when>
   <xsl:otherwise>
     <xsl:value-of select="$result" />
   </xsl:otherwise>
 </xsl:choose>
</xsl:template>

/books/book/author/name : exists
/books/book/name : exists

Hi,

I am trying to achieve the following using XSLT :

I apply a XSLT on my source XML to get a path - say, books/author/name

Now, I want to see if this node exists in another xml. Is there a way by
which this can be achieved using XSLT ?

Sample Source XML : The dots are used as delimiters and will later be
replaced to slashes in the XSLT.

Paths.xml

<Paths>
       <path1>books.book.author.name</path1>
       <path2>books.book.name</path2>
</Paths>

------------------------------------------------------------------------
-------------

Sample Input XML.

Input.xml

<books>
       <book>
               <name>a1</book>
               <price>10</price>
               <author>
                       <name>b1</name>
                       <gender>m</gender>
               </author>
       </book>
       <book>
               <name>a2</book>
               <price>10</price>
               <author>
                       <name>b2</name>
                       <gender>f</gender>
               </author>
       </book>
</books>

The XSLT should first get the path from the paths.xml and search the
Input.xml to see if the node specified by the path exists. Can somebody
please let me know how to go about solving this.

Regards,
BT

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