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    copied!<p>This can be solved pretty easily using XPath. Here's the expression you're looking for: <code>count((.|preceding-sibling::ROLE)[not(@name = preceding-sibling::ROLE/@name)])</code></p> <p>This can be broken down to make it more readable, as I've done in the following XSLT 1.0 stylesheet:</p> <pre><code>&lt;xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"&gt; &lt;xsl:output method="text"/&gt; &lt;!-- don't copy whitespace --&gt; &lt;xsl:template match="text()"/&gt; &lt;xsl:template match="ROLE"&gt; &lt;xsl:variable name="roles-so-far" select=". | preceding-sibling::ROLE"/&gt; &lt;!-- Only select the first instance of each ROLE name --&gt; &lt;xsl:variable name="roles-so-far-unique" select="$roles-so-far[not(@name = preceding-sibling::ROLE/@name)]"/&gt; &lt;xsl:apply-templates select="@name"/&gt; &lt;xsl:text&gt; &lt;/xsl:text&gt; &lt;xsl:value-of select="count($roles-so-far-unique)"/&gt; &lt;xsl:text&gt;&amp;#xA;&lt;/xsl:text&gt; &lt;!-- linefeed --&gt; &lt;/xsl:template&gt; &lt;/xsl:stylesheet&gt; </code></pre> <p>Here's an alternative implementation, using the Muenchian method. First, declare a key:</p> <pre><code>&lt;xsl:key name="roles" match="ROLE" use="@name"/&gt; </code></pre> <p>Then, replace the definition of $roles-so-far-unique with something like this:</p> <pre><code>&lt;!-- Among all the ROLEs having one of the names so far, select only the first one for each name --&gt; &lt;xsl:variable name="roles-so-far-unique" select="../ROLE[@name = $roles-so-far/@name] [generate-id(.) = generate-id(key('roles',@name)[1])]"/&gt; </code></pre> <p>This code, of course, is more complicated. Unless you have a large data set requiring you to speed up processing using the Muenchian method (even then I would test to make sure it buys you anything), you might as well stick with the simpler version above.</p> <p>Finally, in XSLT 2.0, it's much easier. Simple replace the $roles-so-far-unique definition with the following:</p> <pre><code>&lt;!-- Return a list of distinct string values, with duplicates removed --&gt; &lt;xsl:variable name="roles-so-far-unique" select="distinct-values($roles-so-far/@name)"/&gt; </code></pre> <p>I hope this has helped you identify where you went wrong in the various attempts that you mentioned.</p>
 

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