correct namespace for duration sub-types?

Hi Chaps,

I am a bit confused about which is the correct namespace for duration
subtypes, e.g. dayTimeDuration, monthYearDuration etc.

I was under the impression that the correct namespace is
http://www.w3.org/2005/xpath-datatypes 

However when using the latest Saxon 8.9.0.3, it complains if I bind the
duration sub-types to that namespace, with the message -

XPath syntax error at char 29 on line 5 in
{xdt:dayTimeDuration('P2DT0S')}: Cannot find a matching 1-argument
function named {http://www.w3.org/2005/xpath-datatypes}dayTimeDuration()

It is only happy when I bind the duration sub-types to the Schema
namespace - http://www.w3.org/2001/XMLSchema

The following simplified XSLT2 Snippet shows the problem in Saxon. If
you change xdt:dayTimeDuration('P2DT0S') to xs:dayTimeDuration('P2DT0S')
then it works correctly, but is this incorrect behaviour on Saxon's
part? or have I made a mistake? -

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:xdt="http://www.w3.org/2005/xpath-datatypes" version="2.0">
    <xsl:output encoding="UTF-8" media-type="text/xml" version="1.0"
indent="yes"/>
    <xsl:template match="/">
        <xsl:value-of select="xdt:dayTimeDuration('P2DT0S')"/>
    </xsl:template>
</xsl:stylesheet>


Thanks Adam

-- 
Adam Retter

Principal Developer
Devon Portal Project
Room 310
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