<tests>
			<test>
				<one> 1 </one>
				<two> 2 </two>
				<three> 3 </three>
			</test>
			<test>
				<four> 4 </four>
			</test>
			<test>
				<five> 5 </five>
				<six> 6 </six>
				<seven> 7 </seven>
			</test>
		</tests>

			<test>
				<one> 1 </one>
				<two> 2 </two>
				<three> 3 </three>
			</test>

			<test>
				<four> 4 </four>
			</test>

<?xml version="1.0"?>
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	xmlns:msxsl="urn:schemas-microsoft-com:xslt" 
	xmlns:ext="urn:extension-functions" 
	exclude-result-prefixes="msxsl ext">
	<xsl:output method="text" encoding="windows-1251"/>

	<msxsl:script language="JavaScript" implements-prefix="ext">
		function setLen(txt){
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	</msxsl:script>


	<xsl:template match="data">
		<xsl:value-of select="ext:setLen(.)"/>
	</xsl:template>
	
</xsl:stylesheet>

<?xml version="1.0"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
	xmlns:msxsl="urn:schemas-microsoft-com:xslt" 
	xmlns:ext="urn:extension-functions" 
	exclude-result-prefixes="msxsl ext">
	<xsl:output method="xml" indent="yes" encoding="windows-1251"/>

	<msxsl:script language="JavaScript" implements-prefix="ext">
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		return len + ('' + len).length;
		}
	</msxsl:script>

	<xsl:template match="node() | @*">
		<xsl:copy>
			<xsl:apply-templates select="@* | node()"/>
		</xsl:copy>
	</xsl:template>
	
	<xsl:template match="node()[@len]">
		<xsl:variable name="len" select="."/>
		<xsl:copy>
			<xsl:for-each select="*">
				<xsl:attribute name="len">
					<xsl:value-of select="ext:xml($len)"/>
				</xsl:attribute>
				<xsl:copy>
					<xsl:apply-templates select="@* | node()"/>
				</xsl:copy>
			</xsl:for-each>
		</xsl:copy>
	</xsl:template>

</xsl:stylesheet>