Request help in understanding: node instance of sche

Hi Folks,

Apparently I am not correctly understanding this XPath statement:

    if (//test instance of schema-element(test)) then
        //test * 2
    else 'Error'

My understanding of the XPath is this: "If the <test> element in the
input document conforms to the declaration of test in the XML Schema
then multiply its value by 2, otherwise output Error."

I have an XML Schema in which I declare the <test> element.  The <test>
element in the input XML document conforms to the Schema declaration.
So, I expected the XPath statement to execute the if-statement.
Instead, it executes the else-statement.  Thus, the output is: Error.

What am I doing wrong?

I am using the schema-aware version of SAXON, version 8.9.0.4j.  Below
is the stylesheet, XML Schema, and XML document.

Any help would be much appreciated.

/Roger

----------------------------------------------------------
STYLESHEET (test.xsl)

<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                version="2.0">

    <xsl:output method="text"/>

    <xsl:import-schema schema-location="test.xsd"/>

    <xsl:template match="/">

        <xsl:value-of select="if (//test instance of
schema-element(test)) then
                              //test * 2
                              else 'Error'"/>

    </xsl:template>

</xsl:stylesheet>

----------------------------------------------------------
XML SCHEMA (test.xsd)

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified">


    <xs:element name="test" type="xs:integer"/>

</xs:schema>

----------------------------------------------------------
XML DOCUMENT (test.xml)

<?xml version="1.0" encoding="UTF-8"?>
<test xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:noNamespaceSchemaLocation="test.xsd">
   120
</test>