[xsl] inconsistent Preceding-Sibling behaviour when nested in For-Each

[Alan Stein <as2@xxxxxxxxxxx>]

I've observed a reproducible XSL behaviour that I just can't 
understand.  "preceding-sibling", "following-sibling", and conditional 
expressions based on these axes appear to behave oddly when placed in a 
"for-each" element.

 My observations of the unusual behavior within the "for-each" loop:

-- "following-sibling" behaves exactly as I would expect
-- "preceding sibling" unexpectedly always refers to the first sibling in 
the document
-- "if" statements behave erraticly: neither comparisons of current nodes 
to "preceding-sibling" nor comparisons to "following-sibling" appear to 
work completely.

I've listed some sample code below to demonstrate the problem.

Thanks much for any help with this.
  --Alan


Example:

My XML file:

<joblist>
	<person>
		<name>frank</name>
		<job>cook</job>
	</person>
	<person>
		<name>frank</name>
		<job>clean</job>
	</person>
	<person>
		<name>joe</name>
		<job>drive</job>
	</person>
	<person>
		<name>chris</name>
		<job>clean</job>
	</person>
	<person>
		<name>chris</name>
		<job>drive</job>
	</person>
</joblist>


My XSL file:

<xsl:stylesheet version="1.0" 
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"; 
xmlns:fo="http://www.w3.org/1999/XSL/Format";>
	<xsl:template match="joblist">
		<xsl:for-each select="./person">
			++++++++++++++++++++++++++++
			<br/>
			CurName=<xsl:value-of select="./name"/><br/>
			CurJob=<xsl:value-of select="./job"/><br/>
			<br/>
			PrevName=<xsl:value-of select="./preceding-sibling::node()/name"/><br/>
			PrevJob=<xsl:value-of select="./preceding-sibling::node()/job"/><br/>
			NextName=<xsl:value-of select="./following-sibling::node()/name"/><br/>
			NextJob=<xsl:value-of select="./following-sibling::node()/job"/><br/>
			<br/>
			<xsl:if test="./name=./preceding-sibling::node()/name">Name Match with 
Previous<br/></xsl:if>
			<xsl:if test="./name=./following-sibling::node()/name">Name Match with 
Next<br/></xsl:if>
			<xsl:if test="./job=./preceding-sibling::node()/job">Job Match with 
Previous<br/></xsl:if>
			<xsl:if test="./job=./following-sibling::node()/job">Job Match with 
Next<br/></xsl:if>
		</xsl:for-each>
	</xsl:template>
</xsl:stylesheet>


The Unexpected Output:

++++++++++++++++++++++++++++
CurName=frank
CurJob=cook

PrevName=
PrevJob=
NextName=frank
NextJob=clean

Name Match with Next
++++++++++++++++++++++++++++
CurName=frank
CurJob=clean

PrevName=frank
PrevJob=cook
NextName=joe
NextJob=drive

Name Match with Previous
Job Match with Next
++++++++++++++++++++++++++++
CurName=joe
CurJob=drive

PrevName=frank
PrevJob=cook
NextName=chris
NextJob=clean

Job Match with Next
++++++++++++++++++++++++++++
CurName=chris
CurJob=clean

PrevName=frank
PrevJob=cook
NextName=chris
NextJob=drive

Name Match with Next
Job Match with Previous
++++++++++++++++++++++++++++
CurName=chris
CurJob=drive

PrevName=frank
PrevJob=cook
NextName=
NextJob=

Name Match with Previous
Job Match with Previous






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