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    copied!<p><strong>Performing a chain of transformations is used quite often in XSLT applications</strong>, though doing this entirely in XSLT 1.0 requires the use of the vendor-specific <code>xxx:node-set()</code> function. In XSLT 2.0 no such extension is needed as the infamous RTF datatype is eliminated there.</p> <p><strong>Here is an example</strong> (too-simple to be meaningful, but illustrating completely how this is done):</p> <pre><code>&lt;xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:ext="http://exslt.org/common"&gt; &lt;xsl:output omit-xml-declaration="yes" indent="yes"/&gt; &lt;xsl:template match="/"&gt; &lt;xsl:variable name="vrtfPass1"&gt; &lt;xsl:apply-templates select="/*/*"/&gt; &lt;/xsl:variable&gt; &lt;xsl:variable name="vPass1" select="ext:node-set($vrtfPass1)"/&gt; &lt;xsl:apply-templates mode="pass2" select="$vPass1/*"/&gt; &lt;/xsl:template&gt; &lt;xsl:template match="num[. mod 2 = 1]"&gt; &lt;xsl:copy-of select="."/&gt; &lt;/xsl:template&gt; &lt;xsl:template match="num" mode="pass2"&gt; &lt;xsl:copy&gt; &lt;xsl:value-of select=". *2"/&gt; &lt;/xsl:copy&gt; &lt;/xsl:template&gt; &lt;/xsl:stylesheet&gt; </code></pre> <p><strong>when this transformation is applied on the following XML document</strong>:</p> <pre><code>&lt;nums&gt; &lt;num&gt;01&lt;/num&gt; &lt;num&gt;02&lt;/num&gt; &lt;num&gt;03&lt;/num&gt; &lt;num&gt;04&lt;/num&gt; &lt;num&gt;05&lt;/num&gt; &lt;num&gt;06&lt;/num&gt; &lt;num&gt;07&lt;/num&gt; &lt;num&gt;08&lt;/num&gt; &lt;num&gt;09&lt;/num&gt; &lt;num&gt;10&lt;/num&gt; &lt;/nums&gt; </code></pre> <p><strong>the wanted, correct result is produced</strong>:</p> <pre><code>&lt;num&gt;2&lt;/num&gt; &lt;num&gt;6&lt;/num&gt; &lt;num&gt;10&lt;/num&gt; &lt;num&gt;14&lt;/num&gt; &lt;num&gt;18&lt;/num&gt; </code></pre> <p><strong>Explanation</strong>:</p> <ol> <li><p><strong>In the first step the XML document is transformed</strong> and the result is defined as the value of the variable <code>$vrtfPass1</code>. This copies only the <code>num</code> elements that have odd value (not even).</p></li> <li><p><strong>The <code>$vrtfPass1</code> variable, being of type RTF, is not directly usable for XPath expressions</strong> so we convert it to a normal tree, using the EXSLT (implemented by most XSLT 1.0 processors) function <code>ext:node-set</code> and defining another variable -- <code>$vPass1</code> whose value is this tree.</p></li> <li><p><strong>We now perform the second transformation in our chain of transformations</strong> -- on the result of the first transformation, that is kept as the value of the variable <code>$vPass1</code>. Not to mess with the first-pass template, we specify that the new processing should be in a named mode, called "pass2". In this mode the value of any <code>num</code> element is multiplied by two.</p></li> </ol> <p><strong>XSLT 2.0 solution</strong> (no RTFs):</p> <pre><code>&lt;xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:xs="http://www.w3.org/2001/XMLSchema"&gt; &lt;xsl:output omit-xml-declaration="yes" indent="yes"/&gt; &lt;xsl:template match="/"&gt; &lt;xsl:variable name="vPass1" &gt; &lt;xsl:apply-templates select="/*/*"/&gt; &lt;/xsl:variable&gt; &lt;xsl:apply-templates mode="pass2" select="$vPass1/*"/&gt; &lt;/xsl:template&gt; &lt;xsl:template match="num[. mod 2 = 1]"&gt; &lt;xsl:copy-of select="."/&gt; &lt;/xsl:template&gt; &lt;xsl:template match="num" mode="pass2"&gt; &lt;xsl:copy&gt; &lt;xsl:value-of select=". *2"/&gt; &lt;/xsl:copy&gt; &lt;/xsl:template&gt; &lt;/xsl:stylesheet&gt; </code></pre>
 

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