Functional program for "list sum"

I am trying to implement a "integer sum" function in a
functional manner .. My stylesheet so far is -

<?xml version="1.0"?> 
<xsl:stylesheet
xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
               
xmlns:xs="http://www.w3.org/2001/XMLSchema"
                xmlns:fn="http://whatever"
                version="1.0">
 
 <xsl:output method="text" /> 

 <xsl:template match="/">
    <xsl:variable name="result"
select="fn:listSum(null,(1,2,3))" />
    <xsl:value-of select="$result" />
 </xsl:template>
 
 <xsl:function name="fn:listSum" as="xs:integer">
    <xsl:param name="num" as="xs:integer" />
    <xsl:param name="list" as="xs:integer+" />
    <xsl:sequence
select="fn:listSum($num,$list[position() &gt; 1])" />
 </xsl:function>
 
</xsl:stylesheet>

But I am getting following error with Saxon 8.4 ..

"Warning: Running an XSLT 1.0 stylesheet with an XSLT
2.0 processor
Error on line 10 of file:/C:/xml/xsleg/xslt/fp.xsl:
  XPTY0004: An empty sequence is not allowed as the
first argument of fn:listSum
()
Transformation failed: Run-time errors were reported"
..

Can someone please help me ..?

Regards,
Mukul


		
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