schematron localfunctions gives error - xslt

Question

I have schematron file which contains xsl function.
I get this error : "the function functionName was not found in namespace localFunctions"
Here is my schematron codes:
<?xml version="1.0" encoding="UTF-8"?>
<schema xmlns="http://purl.oclc.org/dsdl/schematron"
xmlns:sch="http://purl.oclc.org/dsdl/schematron"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:fct="localFunctions"
queryBinding="xslt2" >
<ns prefix="gl-plt" uri="http://www.xbrl.org/int/gl/plt/2010-04-16" />
<ns prefix="gl-cor" uri="http://www.xbrl.org/int/gl/cor/2006-10-25" />
<ns prefix="gl-bus" uri="http://www.xbrl.org/int/gl/bus/2006-10-25" />
<ns prefix="xbrli" uri="http://www.xbrl.org/2003/instance" />
<ns prefix="edefter" uri="http://www.edefter.gov.tr" />
<ns prefix="fct" uri="localFunctions" />
<title></title>
<!-- <gl-cor:accountingEntries> elemanı bir <gl-cor:entityInformation> elemanı içermelidir. -->
<pattern id="accountingentries">
<rule context="/edefter:defter/xbrli:xbrl/gl-cor:accountingEntries">
<let name="accoundMainIdList" value="gl-cor:entryHeader/gl-cor:entryDetail[1]/gl-cor:account/normalize-space(gl-cor:accountMainID)"/>
<assert test="fct:isSorted($accoundMainIdList)">Büyük defterde hesaplar, ana hesap numarası bazında sıralı olmalıdır.</assert>
</rule>
</pattern>
<xsl:function name="fct:isSorted" as="xs:boolean">
<xsl:param name="accoundMainIdList" as="xs:string*"/>
<xsl:variable name="sortedAccountMainIdList" as="xs:string*">
<xsl:for-each select="$accoundMainIdList">
<xsl:sort/>
<xsl:value-of select="."/>
</xsl:for-each>
</xsl:variable>
<xsl:variable name="s1">
<xsl:value-of select="string-join($accoundMainIdList,'|')"/>
</xsl:variable>
<xsl:variable name="s2">
<xsl:value-of select="string-join($sortedAccountMainIdList,'|')"/>
</xsl:variable>
<xsl:choose>
<xsl:when test="$s1 = $s2">
<xsl:value-of select="true()"/>
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="false()"/>
</xsl:otherwise>
</xsl:choose>
</xsl:function>
</schema>
Why isSorted xsl function not found in namespace ?

Answer 1

I'm assuming that you are aware that the conventional method of running Schematron schemas is to process them using XSLT to generate an XSLT stylesheet which can be executed against your XML instance.
Looking on github, the XRouters Schematron projects is using a very old version of the standard XSLT stylesheets from http://www.schematron.com/. These are XSLT 1.0 stylesheets and are not capable of generating XSLT 2.0 stylseheets.
The xsl:function element you are trying to use is part of XSLT 2.0. Given that your tool is generating XSLT 1.0 it seems very unlikely that your XSLT 2.0 function will operate.
If you want to try an approach that may be more successful, may I suggest that you obtain a copy of Saxon HE (the .net version) from http://saxon.sf.net/. You can then build a simple set of XSLT transforms that will give you more of a chance of getting what you want.

Answer 2

I think #Nic's answer is in the right direction, but missed the mark.
Although the standard way of running schematron schemas against XML documents is to convert them to XSLT, that approach has a number of drawbacks (speed and having validation report you can process programmatically are two primary ones).
The XRouter SchemaTron is a native .NET implementation of ISO schematron. It doesn't convert the schematron schemas to XSLT stylesheets -- it parses them in memory and then processes each pattern/rule/assert to detect violations.
The problem is certainly rooted in a lack of XSLT2 support, but is not related at all to XSLT schematron stylesheets (they arent used, and are included in the project only as reference). Schematron specification doesn't require XSLT2 (or XPATH2) -- it leaves the query language to the schematron rules file. The branch you were using was probably the one delivering XPATH2 support via "Lightweight XPath2 for .NET", which doesn't support XSLT2.
I recommend using the branch of the project integrated with XmlPrime, with supports XSLT2. We're using that version with great success.