Saxon

One of our users posted an example here:

https://www.oxygenxml.com/forum/post44286.html#p44283

So the test.xml is:

<root filePath="../../../grammars/efl/infoCommentaire/xf_infoCommentaire.srng"/>

and the test.xsl is:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:xd="http://www.oxygenxml.com/ns/doc/xsl"
    xmlns:xs="http://www.w3.org/2001/XMLSchema"
    xmlns:els="http://www.lefebvre-sarrut.eu/ns/els"
    xmlns:functx="http://www.functx.com"
    exclude-result-prefixes="#all"
    version="2.0">
    
    <!--<xsl:include href="functx.xsl"/>-->
    
    <!--==========================================-->
    <!--MAIN-->
    <!--==========================================-->
    
    <xsl:template match="/*">
        <xsl:value-of select="els:getFileName(@filePath)"/>
    </xsl:template>
    
    <!--==========================================-->
    <!--FUNCTIONS-->
    <!--==========================================-->
    
    <xsl:function name="els:getFileName" as="xs:string">
        <xsl:param name="filePath" as="xs:string?"/>
        <xsl:param name="withExt" as="xs:boolean"/>
        <xsl:variable name="fileNameWithExt" select="functx:substring-after-last-match($filePath,'/')"/>
        <xsl:variable name="fileNameNoExt" select="functx:substring-before-last-match($fileNameWithExt,'\.')"/>
        <!--DEBUG-->
        <xsl:message>filePath = <xsl:value-of select="$filePath"/></xsl:message>
        <xsl:variable name="localString" select="'../../../grammars/efl/infoCommentaire/xf_infoCommentaire.srng'" as="xs:string"/>
        <xsl:message>$localString = $filePath  is <xsl:value-of select="$localString = $filePath"/></xsl:message>
        <xsl:message>test1 (with $filePath) = <xsl:value-of select="functx:substring-after-last-match($filePath,'/')"/></xsl:message>
        <xsl:message>test2 (with $localString) = <xsl:value-of select="functx:substring-after-last-match($localString,'/')"/></xsl:message>
        <!--/DEBUG-->
        <xsl:variable name="ext" select="els:getFileExt($fileNameWithExt)"/>
        <xsl:sequence select="concat('', $fileNameNoExt, if ($withExt) then (concat('.',$ext)) else (''))"/>
    </xsl:function>
    
    <!--1 arg signature-->
    <xsl:function name="els:getFileName" as="xs:string">
        <xsl:param name="filePath" as="xs:string?"/>
        <xsl:sequence select="els:getFileName($filePath,true())"/>
    </xsl:function>
    
    <xsl:function name="els:getFileExt" as="xs:string">
        <xsl:param name="filePath" as="xs:string?"/>
        <xsl:sequence select="concat('',functx:substring-after-last-match($filePath,'\.'))"/>
    </xsl:function>
    
    <!--==========================================-->
    <!--FUNCTX (copy of used functions)-->
    <!--==========================================-->
    <xsl:function xmlns:functx="http://www.functx.com" name="functx:substring-after-last-match" as="xs:string">
        <xsl:param name="arg" as="xs:string?"/>
        <xsl:param name="regex" as="xs:string"/>
        <xsl:sequence select=" replace($arg,concat('^.*',$regex),'') "/>
    </xsl:function>
    
    <xsl:function xmlns:functx="http://www.functx.com" name="functx:substring-before-last-match" as="xs:string?">
        <xsl:param name="arg" as="xs:string?"/>
        <xsl:param name="regex" as="xs:string"/>
        <xsl:sequence select=" replace($arg,concat('^(.*)',$regex,'.*'),'$1') "/>
    </xsl:function>
    
</xsl:stylesheet>

Running Saxon EE from the command line you obtain:

<?xml version="1.0" encoding="UTF-8"?>srng.srng

but running Saxon PE you obtain:

<?xml version="1.0" encoding="UTF-8"?>xf_infoCommentaire.srng