Question

I have an xml file like this:

<root>     <item>         <name>one</name>         <status>good</status>     </item>     <item>         <name>two</name>         <status>good</status>     </item>     <item>         <name>three</name>         <status>bad</status>     </item>     <item>         <name>four</name>         <status>ugly</status>     </item>     <item>         <name>five</name>         <status>bad</status>     </item> </root> 

I want to transform this using XSLT to get something like:

<root>     <items><status>good</status>         <name>one</name>         <name>two</name>     </items>     <items><status>bad</status>         <name>three</name>         <name>five</name>     </items>     <items><status>ugly</status>         <name>four</name>     </items> </root> 

In other words, I get a list of items, each with a status, and I want to turn it into a list of statuses, each with a list of items.

My initial thought was to do apply-templates matching each status type in turn, but that means I have to know the complete list of statuses. Is there a better way to do it?

Thanks for any help.

Answer 1

Muench to the rescue!

<?xml version='1.0' encoding='UTF-8'?> <xsl:stylesheet version='1.0' xmlns:xsl='http://www.w3.org/1999/XSL/Transform'>      <xsl:output method='xml' indent='yes' encoding='UTF-8'/>      <xsl:key name='muench' match='/root/item/status' use='.'/>      <xsl:template match='/'>         <root>         <xsl:for-each select='/root/item/status[generate-id() = generate-id(key('muench',.)[1])]'>             <xsl:call-template name='pivot'>                 <xsl:with-param name='status' select='.'/>             </xsl:call-template>         </xsl:for-each>         </root>     </xsl:template>      <xsl:template name='pivot'>         <xsl:param name='status'/>         <items>             <status><xsl:value-of select='$status'/></status>             <xsl:for-each select='/root/item[status=$status]'>                 <name><xsl:value-of select='name'/></name>             </xsl:for-each>         </items>     </xsl:template>  </xsl:stylesheet>