Standard problem?

["Nestel, Frank" <frank dot nestel at coi dot de>]

Hi there,

I think this might be a standard problem: Having an XSL
which generates a certain subtree of a tree. I mean the
case, usually used in web site navigation.

E.g. having an xml which contains my site structure, 
like:

    <NODE id="A">
        <NODE id="A1"/>
        <NODE id="A2"/>
        <NODE id="A3">
            <NODE id="A3i"/>
            <NODE id="A3ii"/>
        </NODE>
    </NODE>
    <NODE id="B"/>
    <NODE id="C">
        <NODE id="C1"/>
        <NODE id="C2"/>
    </NODE>

I want to show an "extended branch" to every node. Eg. to
node "A3i", I'd like to have (except typos)

    <NODE id="A">
        <NODE id="A3">
            <NODE id="A3i"/>
            <NODE id="A3ii"/>
        </NODE>
    </NODE>
    <NODE id="B"/>
    <NODE id="C"/>

To Node B I'd like top get

    <NODE id="A"/>
    <NODE id="B"/>
    <NODE id="C"/>

To Node A3, this would result give

    <NODE id="A">
        <NODE id="A1"/>
        <NODE id="A2"/>
        <NODE id="A3">
            <NODE id="A3i"/>
            <NODE id="A3ii"/>
        </NODE>
    </NODE>
    <NODE id="B"/>
    <NODE id="C"/>

And so on. 

This is, to every node I'd like to have
all its parents and their siblings, I'd also like to
have the node and it's siblings and the direct 
childs of the node. 

The solution I currently have is only half way through
and looks somewhat complicated: 

	<xsl:stylesheet
	 xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"
	>
	<xsl:output indent="yes"/>
	
	<xsl:strip-space elements="*"/>
	
	<xsl:param name="page">A1i</xsl:param>
	
	<xsl:template match="/">
	    <xsl:value-of select="$page"/>
	    <xsl:for-each select="//NODE">
	        <xsl:apply-templates select="." mode="b"/>
	    </xsl:for-each>
	</xsl:template>

	<xsl:template match="NODE" mode="b">
	    <xsl:if test="@id=$page">
	        <xsl:variable name="dest" select="."/>
	        <xsl:variable name="destid" select="@id"/>
	        <xsl:for-each
select="ancestor::NODE/preceding-sibling::NODE|ancestor::NODE|ancestor::NODE
/following-sibling::NODE|preceding-sibling::NODE|following-sibling::NODE|.|c
hild::NODE">
	            <NODE>
		            <xsl:value-of
select="count(ancestor::NODE)"/>:<xsl:if test="@id = $destid">#</xsl:if>
	            <xsl:value-of select="@id"/>
      	      </NODE>
	        </xsl:for-each>
	    </xsl:if>
	</xsl:template>

	</xsl:stylesheet>	

Though I'm pretty sure, I could make it work and it is kind of
my personal homework, I still wonder if someone of the gurus
could come up with an instant and nice solution to this???

Thank you,

Frank 


 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list