Yes, this is XPath 2.0. I don't bother with 1.0 if I can, because it is soooo far behind 2.0.
data: <data attr="1" />
xsl:
<?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" exclude-result-prefixes="xs" version="2.0">
<xsl:template match="/data">
<one>
<xsl:value-of select="@attr = (2,3,4)" />
</one>
<two>
<xsl:value-of select="(@doesntexist,2)[1]" />
</two>
</xsl:template>
</xsl:stylesheet>
gives: <one>false</one><two>2</two>
