nkunapa wrote:
> Hi:
>  Is there a way in XPATH to find the nearest node of the node in
> context with a certain attribute value. Here is my problem. I have the
> following XML and I am trying to add all the nodes with attribute value
> 
> LNum=1 as child nodes of the nearest node above it with attribute
> LNum=0....and add all the nodes with attribute value LNum=2 as child
> nodes of the nearest node above it with attribute LNum=1 and so on. The

Hi,

Have you thought about selecting all suitable nodes in the 
preceding-sibling axis, and then pick the first of them? That should be 
the nearest above (unless I have messed up something). The FIRST is 
becuase the preceding-sibling is reverse; the first is the nearest to 
the context.

preceding-sibling::*[@LNum=$MyLNumMinus1][1]

I tried it in an XSLT (just because that's all I have working right now 
for evaluating XPath):


<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
version="1.0">

<xsl:template match="thing">
   <xsl:variable name="myLNumMinus1" select="@LNum - 1"/>
   <xsl:variable name="catch" 
select="preceding::*[@LNum=$myLNumMinus1][1]/@name"/>
     <xsl:if test="$catch">
     This node had a suitable ancestor:
     <thing myName="{@name}" myLNum="{@LNum}" 
ImLookingFor="{$myLNumMinus1}" 
my-nearest-predecessor-with-that-LNum="{$catch}"/>
     </xsl:if>
   <xsl:apply-templates/>
</xsl:template>
</xsl:stylesheet>


For input file:

<?xml version="1.0"?>
<thing name="ancestor0" LNum="0">
   <thing name="ancestor1" LNum="0">
     <thing name="ancestor2" LNum="0">
       <thing name="a-predecessor-but-not-an-ancestor-to-the-successor" 
LNum="1"/>
       <thing name="depth3" LNum="1">
         <thing name="depth4" LNum="2"/>
         <thing name="depth4, again" LNum="1"/>
       </thing>
       <thing name="depth3, again" LNum="2"/>
     </thing>
   </thing>
</thing>

I got
[dongfang@granada nearest-ancestor]$ xsltproc nearest-predecessor.xsl 
things.xml
<?xml version="1.0"?>
     This node had a suitable ancestor:
     <thing myName="depth4" myLNum="2" ImLookingFor="1" 
my-nearest-predecessor-with-that-LNum="a-predecessor-but-not-an-ancestor-to-the-successor"/>
     This node had a suitable ancestor:
     <thing myName="depth3, again" myLNum="2" ImLookingFor="1" 
my-nearest-predecessor-with-that-LNum="depth4, again"/>
[dongfang@granada nearest-ancestor]$


With your "flat" documents it doesn't matter whether you use precesing 
or preceding-sibling; it's the same.

Soren