Filtering data using another customs markups and stylesheet

[akuash]

I am trying to write a document which could help in filtering data from another XML document. E.g. <filter> <what> <include> <marital_staus/> <ms>single</ms> <!--nog = no of groups--> <include> <memberofgroups/> <gn>Football club</gn> <!--user is a member of this club--> </include> </include> </what></filter> What I want this code to do is to choose, first, the users who are members of Football club, and then out of those, chose the users who are single. But I cannot figure out how to write a stylesheet for this. I wrote this: <xsl:template name="temp"> <xsl:param name="a1"/> <xsl:param name="pro"/> <xsl:choose> <xsl:when test="$op = 'marital_status'"> <xsl:for-each select="/document/users/user"> <xsl:if test="marital_status=$a1"> <xsl:value-of select="."/> </xsl:if> </xsl:for-each> </xsl:when> <xsl:when test="$op = 'memberofgroups'"> <xsl:for-each select="/document/users/user"> <xsl:for-each select="./groups/member_of_group"> <xsl:if test=".=$a1"> <xsl:value-of select="."/> </xsl:if> </xsl:for-each> </xsl:for-each> </xsl:when> </xsl:choose> </xsl:template> <xsl:template match="include"> <xsl:call-template name="temp"> <xsl:with-param name="a1"> <xsl:apply-templates select="*[2]"/> </xsl:with-param> </xsl:call-template> </xsl:template> While calling the template I pass the correct values I suppose. Problem is I get all the users who are single, plus all the users who are members of that particular group. However I want single users who are also member of Football club. I don't want the stylesheet to be hard-coded, because I also want to do filtering based on other elements. I can not figure out how can I save the filtered elements into something which could be used as an input for the next XPath expression. Or am I making some mistake while writing the constraints for filtering the document. Or could there be any other more appropriate way of writing a document for filtering? I will much appreciate your help. And I have one xml document "document" and two elements "filter" and "users".

Edited May 20, 2012 by akuash