Lech,



Since you are using XSLT 2.0, you can fall back to the actual name in 
the same XPath you use to look up a new name:



<xsl:element name="{($maps[@old = 
local-name(current())]/@new),local-name())[1]}">



This uses the idiom ($a, $b)[1] whereby the first item in $b is used 
when $a is empty.



If you want to generate a warning message, this is done easily with a 
conditional:



<xsl:if test="empty($maps[@old = local-name(current())]/@new)">
  ... generate your message ...
</xsl:if>

(A stricter test would check if your mapped name were a valid Qname, 
just in case.)



I hope this helps,
Wendell


At 09:41 AM 4/1/2008, you wrote:
Hi.



I'm doing a simple transformation, substituting some tags with
different named ones and keeping the rest the same.
Since there are many strange cases, I'd like to keep the mapping in
the intermediate XML file (to keep the XSL clean), such as maps.xml:

<?xml version="1.0" encoding="UTF-8"?>
<maps>
    <map old="old-tag1" new="tag1"></map>
    <map old="old-strange-tag2" new="tag2"></map>
    <!-- <map old="" new=""></map> -->
</maps>

and then transform using:



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



<xsl:variable name="maps" 
select="document('maps.xml')/maps/map"></xsl:variable>



<xsl:template match="*">
    <xsl:element name="{$maps[@old = local-name(current())]/@new}">
        <xsl:apply-templates select="node()|@*"/>
    </xsl:element>
</xsl:template>

</xsl:stylesheet>



But when I run that through Saxon 9B it says "Invalid element name.
Invalid QName {}" URL: http://www.w3.org/TR/xslt20/#err-XTDE0820

My source file contains both the elements matched by map and other 
elements too.




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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
Mulberry Technologies, Inc.                http://www.mulberrytech.com
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Suite 207                                          Phone: 301/315-9631
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