xslt get preceding node value

Question

I am trying to access the previous node value and compare it with current node value if they match. Please let me know where i am going wrong.

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<nums>
  <num>02</num>
  <num>02</num>
  <num>03</num>
  <num>04</num>
  <num>05</num>
  <num>06</num>
  <num>06</num>
  <num>08</num>
  <num>09</num>
  <num>10</num>
</nums>

XSLT:

<xsl:stylesheet version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>
 <xsl:strip-space elements="*"/>
 <xsl:template match="node()|@*">
     <xsl:copy>
       <xsl:apply-templates select="node()|@*"/>
     </xsl:copy>
 </xsl:template>
 <xsl:template match="/*">
  <nums>
   <xsl:apply-templates select=
       "num[not(preceding-sibling::node()[1]=node()]"/>
  </nums>
 </xsl:template>
</xsl:stylesheet>

I am trying to fetch the current num values which have different value compared to previous node values. What should be my condition in templates?

Answer 1

Your condition should be expressed as:

<xsl:apply-templates select="num[not(preceding-sibling::node()[1] = .)]"/>

or - preferably - as:

<xsl:apply-templates select="num[not(preceding-sibling::num[1] = .)]"/>

However, this is not a good method to remove duplicates - see here why: http://www.jenitennison.com/xslt/grouping/muenchian.html