Where do I put an XSL function in an XSL document? - xslt

I have an XSL style sheet for which I need to add some custom string manipulation using an xsl:function. But I am having trouble trying to work out where to put the function in my document.
My XSL simplified looks like this,
<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:my="myFunctions" xmlns:d7p1="http://schemas.microsoft.com/2003/10/Serialization/Arrays" xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:import href="Master.xslt"/>
<xsl:template match="/">
<fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
<!-- starts actual layout -->
<fo:page-sequence master-reference="first">
<fo:flow flow-name="xsl-region-body">
<!-- this defines a title level 1-->
<fo:block xsl:use-attribute-sets="heading">
HelloWorld
</fo:block>
</fo:flow>
</fo:page-sequence>
</fo:root>
</xsl:template>
</xsl:stylesheet>
And I want to put in a simple function, say,
<xsl:function name="my:helloWorld">
<xsl:text>Hello World!</xsl:text>
</xsl:function>
But I cannot work out where to put the function, when I put it under the node I get an error saying 'xsl:function' cannot be a child of the 'xsl:stylesheet' element., and if I put it under the node I get a similar error.
Where should I put the function? Idealy I would like to put my functions in an external file and import them into my xsl files.

There is no xsl:function in XSL version 1.0. You have to create a named template
<xsl:template name="helloWorld">
<xsl:text>Hello World!</xsl:text>
</xsl:template>
(...)
<xsl:template match="something">
<xsl:call-template name="helloWorld"/>
</xsl:template>

You can upgrade the stylesheet version to 2.0
Then in stylesheet declaration specify as
<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:func="http://www.**.com">
** Your choice you can specify anything as your wish
then below this specify your function
<xsl:function name="func:helloWorld">
<xsl:text>Hello World!</xsl:text>
</xsl:function>
Then in template you can use it as
<xsl:template match="/">
<xsl:value-of select="func:helloWorld"/>
</xsl:template>

Related

How to create template to match based upon an XSLT parameter

I'm trying to create a standard-use XSLT that will perform a given task based upon a user-provided XPATH expression as an XSLT parameter.
That is, I need something like this:
<xsl:template match="$paramContainingXPATH">
<!-- perform the task on the node(s) in the given xpath -->
</xsl:template>
For example, suppose I have some XML:
<xml>
<nodeA>whatever</nodeA>
<nodeB>whatever</nodeB>
<nodeC>whatever</nodeC>
<nodeD>whatever</nodeD>
<nodeE>whatever</nodeE>
</xml>
The XSLT needs to transform just a node or nodes matching a provided XPATH expression. So, if the xslt parameter is "/xml/nodeC", it processes nodeC. If the xslt parameter is "*[local-name() = 'nodeC' or local-name() = 'nodeE']", it processes nodeC and nodeE.
This should work for absolutely any XML message. That is, the XSLT cannot have any direct knowledge of the content of the XML. So, it could be a raw XML, or a SOAP Envelope.
I was guessing I might need to grab all the nodes matching the xpath, and then looping over them calling a named template, and using the standard identity template for all other nodes.
All advice is appreciated.
If you really need that feature with XSLT 1.0 or 2.0 then I think you should consider writing one stylesheet that takes that string parameter with the XPath expression and then simply generates the code of a second stylesheet where the XPath expression is used as a match pattern and the other needed templates like the identity template are included statically. Dynamic XPath evaluation is only available in XSLT 3.0 or in earlier versions as a proprietary extension mechanism.
You cannot match a template using a parameter - but you can traverse the tree and compare the path of each node with the given path. Here's a simple example:
XSLT 1.0
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:param name="path" select="'/world/America/USA/California'"/>
<xsl:template match="/">
<root>
<xsl:apply-templates select="*"/>
</root>
</xsl:template>
<xsl:template match="*">
<xsl:variable name="path-to-me">
<xsl:for-each select="ancestor-or-self::node()">
<xsl:value-of select="name()" />
<xsl:if test="position()!=last()">
<xsl:text>/</xsl:text>
</xsl:if>
</xsl:for-each>
</xsl:variable>
<xsl:if test="$path=$path-to-me">
<xsl:call-template name="action"/>
</xsl:if>
<xsl:apply-templates select="*"/>
</xsl:template>
<xsl:template name="action">
<return>
<xsl:value-of select="." />
</return>
</xsl:template>
</xsl:stylesheet>
Applied to a slightly more ambitious test input of:
<world>
<Europe>
<Germany>1</Germany>
<France>2</France>
<Italy>3</Italy>
</Europe>
<America>
<USA>
<NewYork>4</NewYork>
<California>5</California>
</USA>
<Canada>6</Canada>
</America>
</world>
the result will be:
<?xml version="1.0" encoding="UTF-8"?>
<root>
<return>5</return>
</root>
This could be made more efficient by passing the accumulated path as a parameter of the recursive template, so that each node needs only to add its own name to the chain.
Note:
The given path must be absolute;
Predicates (including positional predicates) and attributes are not implemented in this. They probably could be, with a bit more effort;
Namespaces are ignored (I don't see how you could pass an XPath as a parameter and include namespaces anyway).
If your processor supports an evaluate() extension function, you could forgo the calculated text path and test for intersection instead.
Edit:
Here's an example using EXSLT dyn:evaluate() and set:intersection():
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:dyn="http://exslt.org/dynamic"
xmlns:set="http://exslt.org/sets"
extension-element-prefixes="dyn set">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:param name="path" select="'/world/America/USA/California'"/>
<xsl:variable name="path-set" select="dyn:evaluate($path)" />
<xsl:template match="/">
<root>
<xsl:apply-templates select="*"/>
</root>
</xsl:template>
<xsl:template match="*">
<xsl:if test="set:intersection(. , $path-set)">
<xsl:call-template name="action"/>
</xsl:if>
<xsl:apply-templates select="*"/>
</xsl:template>
<xsl:template name="action">
<return>
<xsl:value-of select="." />
</return>
</xsl:template>
</xsl:stylesheet>
Note that this will also work with with paths like:
/world/America/USA/*[2]
//California
and many others that the text comparison method could not accommodate.
I'm sending the element name as a param to the XSLT
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:xs="http://www.w3.org/2001/XMLSchema" version="2.0">
<xsl:output method="xml"/>
<xsl:param name="user"/>
<xsl:template match="/">
<xsl:call-template name="generic" />
</xsl:template>
<xsl:template name="generic">
<count><xsl:value-of select="count(.//*[local-name()=$user])"/></count>
</xsl:template>
</xsl:stylesheet>
I hope this could help!

XSL namespace issue

I have an XSL that is transforming one XSD into another XSD that has slightly different formatting. (Basically, the target file will be normalized). The other major difference in the target is adding a default namespace and a target namespace. I'm having trouble actually getting the namespace in. Here is a snippet of my XSL:
<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:xsd="http://www.w3.org/2001/XMLSchema" version="1.0">
<xsl:output method="xml" version="1.0" encoding="UTF-8"/>
<xsl:variable name="Unions" select="'Yes'"/>
<xsl:variable name="myname" select="//Table/Name"/>
<xsl:variable name="namespace" select="concat('http://mynamespace/', $myname)"/>
<xsl:template match="/">
<xsl:element name="xsd:schema" namespace="http://www.w3.org/2001/XMLSchema" xmlns="$namespace"
<xsl:attribute name="targetNamespace">
<xsl:value-of select="$namespace"/>
</xsl:attribute>
<xsl:attribute name="elementFormDefault">qualified</xsl:attribute>
<xsl:attribute name="attributeFormDefault">unqualified</xsl:attribute>
...
</xsl:element>
</xsl:template>
</xsl:stylesheet>
And this is what I'm getting:
<?xml version="1.0" encoding="utf-8"?>
<xsd:schema targetNamespace="http://mynamespace/somename" elementFormDefault="qualified" attributeFormDefault="unqualified" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="">
...
</xsd:schema>
And xmlns="$namespace" is tagged on to every child node. I'm no absolute expert on XSLT. I have not had to develop it myself because BizTalk maps generate all of it for you, but this XSL was more complex than I could get BizTalk maps to handle.
Oh, and I'm limited to XSLT 1.0
Generating namespace nodes with dynamically generated values is something XSLT 1 can't really do. XSLT 2 adds xsl:namespace specifically to construct such things.
You said you are stuck at XSLT 1. Do you have EXSLT or any other extension namespace available that gives you the node-set() extension? If so you can go
<xsl:template match="/">
<xsl:variable name="x">
<xsl:element name="x" namespace="{$namespace}">
<xsl:element name="xsd:schema" namespace="http://www.w3.org/2001/XMLSchema">
....
</xsl:variable>
<xsl:copy-of select="xx:node-set($x)/*/*"/>
</xsl:template>
Creating a spurious element <x> in the desired namespace, this forces the namespace node on to its child xs:schema element which you can extract if you have a node-set extension function.

XSLT key() lookup

I'm trying out a sample of look-up tables in XSLT and am not able to get it to work
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output method="xml" />
<xsl:key name="classification-lookup" match="classification" use="id" />
<xsl:variable name="classification-top" select="document('')/*/classifications" />
<xsl:template match="BusinessListing">
<listing>
<id>
<xsl:value-of select="id" />
</id>
<xsl:apply-templates select="$classification-top">
<xsl:with-param name="curr-label" select="." />
</xsl:apply-templates>
</listing>
</xsl:template>
<xsl:template match="classifications">
<xsl:param name="curr-label" />
<category>
<xsl:value-of select="key('classification-lookup', $curr-label/listingData/classifications/classificationId)/description" />
</category>
</xsl:template>
<classifications>
<classification>
<id>7981</id>
<description>Category1</description>
</classification>
<classification>
<id>7982</id>
<description>Category2</description>
</classification>
<classification>
<id>7983</id>
<description>Category3</description>
</classification>
<classification>
<id>7984</id>
<description>Category4</description>
</classification>
</classifications>
</xsl:stylesheet>
and the source is as below .
<?xml version="1.0"?>
<BusinessListings>
<BusinessListing>
<id>1593469</id>
<listingData>
<classifications>
<classificationId>7982</classificationId>
<classificationId>7983</classificationId>
</classifications>
</listingData>
</BusinessListing>
</BusinessListings>
In the result below , The category is empty but I need the Classification Id from the source to be matched with the id in the classification tag and the category generated .
<?xml version="1.0" encoding="UTF-8"?>
<listing>
<id>1593469</id> -- Empty I need the Category2 and Category3 here
<category/>
</listing>
I know that I may be wide off mark but I've just started off with XSLT and referred the sample here http://www.ibm.com/developerworks/xml/library/x-xsltip.html . Thanks for the help .
Your XSLT stylesheet contains an error -- according to spec, any child-element of xsl:stylesheet (aka top-level element) must be in a non-null namespace:
"*In addition, the xsl:stylesheet
element may contain any element not
from the XSLT namespace, provided that
the expanded-name of the element has a
non-null namespace URI. "
If the XSLT processor you are using doesn't raise an error, then it is non-compliant and buggy and shouldn't be used. Find and use a compliant XSLT processor (I am using .NET XslCompiledTransform, Saxon 6.5.5, ..., etc).
There are other errors, too.
Solution:
Define a new namespace with prefix (say) "x:":
Change the embedded <classifications> to <x:classifications> -- now this conforms to the Spec.
Perform more changes to the code until you get this transformation:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:x="my:x" exclude-result-prefixes="x">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:key name="classification-lookup" match="classification"
use="id" />
<xsl:template match="BusinessListing">
<listing>
<id>
<xsl:value-of select="id" />
</id>
<xsl:apply-templates/>
</listing>
</xsl:template>
<xsl:template match="classificationId">
<xsl:variable name="vCur" select="."/>
<xsl:for-each select="document('')">
<category>
<xsl:value-of select=
"key('classification-lookup',$vCur)/description" />
</category>
</xsl:for-each>
</xsl:template>
<xsl:template match="text()"/>
<x:classifications>
<classification>
<id>7981</id>
<description>Category1</description>
</classification>
<classification>
<id>7982</id>
<description>Category2</description>
</classification>
<classification>
<id>7983</id>
<description>Category3</description>
</classification>
<classification>
<id>7984</id>
<description>Category4</description>
</classification>
</x:classifications>
</xsl:stylesheet>
.4. In the above code notice the line: <xsl:for-each select="document('')"> .
The purpose of this is to make the stylesheet the current document. The key() function operates only on the current document and if you want the embedded classification elements to be indexed and used, you must change the current document (usually in this way). In XSLT 2.0 the key() function allows a 3rd argument which is a node from the document whose index should be used.
When this transformation is applied to the provided XML document:
<BusinessListings>
<BusinessListing>
<id>1593469</id>
<listingData>
<classifications>
<classificationId>7982</classificationId>
<classificationId>7983</classificationId>
</classifications>
</listingData>
</BusinessListing>
</BusinessListings>
the wanted, correct result is produced:
<listing>
<id>1593469</id>
<category>Category2</category>
<category>Category3</category>
</listing>

How can I select nodes from a tree whose markup is stored in a variable?

Consider the following XSLT script:
<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" encoding="iso-8859-1"/>
<xsl:variable name="stringmap">
<map>
<entry><key>red</key><value>rot</value></entry>
<entry><key>green</key><value>gruen</value></entry>
<entry><key>blue</key><value>blau</value></entry>
</map>
</xsl:variable>
<xsl:template match="/">
<!-- IMPLEMENT ME -->
</xsl:template>
</xsl:stylesheet>
I'd like this script to print redgreenblue.
Is there any way to treat the XML markup which is stored in the stringmap variable as a document of its own which I can run XPath queries on? I'm basically looking for something like
<xsl:for-each select="document($stringmap)/map/entry">
<xsl:value-of select="key"/>
</xsl:for-each>
(except that the document() function expects an URI).
Motivation: I have various long <xsl:choose> elements which map a given string to another string. I'd like to replace all those with a single template which takes a 'map' argument (which is a simple XML document). My hope is that I can then replace the <xsl:choose> with a simple statement like <xsl:value-of select="$stringmap/map/entry/value[../key='$givenkey']"/>
I'm using XSLT 1.0 using xsltproc.
You're almost right, using document('') will allow you to process node sets inside the current stylesheet:
<xsl:for-each select="document('')/xsl:stylesheet/xsl:variable[#name='stringmap']/map/entry">
<xsl:value-of select="key"/>
</xsl:for-each>
It's not necessary to define the map node set as a variable in this case:
<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet xmlns:data="some.uri" version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<data:map>
<entry><key>red</key><value>rot</value></entry>
<entry><key>green</key><value>gruen</value></entry>
<entry><key>blue</key><value>blau</value></entry>
</data:map>
<xsl:template match="/">
<xsl:for-each select="document('')/xsl:stylesheet/data:map/entry">
<xsl:value-of select="key"/>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
If you do not use xsl:variable as a wrapper, you must remember that a top level elements must have a non null namespace URI.
In XSLT 2.0 it would've been possible to just iterate over the content in a variable:
<xsl:variable name="map">
<entry><key>red</key><value>rot</value></entry>
<entry><key>green</key><value>gruen</value></entry>
<entry><key>blue</key><value>blau</value></entry>
</xsl:variable>
<xsl:template match="/">
<xsl:for-each select="$map/entry">
<xsl:value-of select="key"/>
</xsl:for-each>
</xsl:template>
A posting by M. David Peterson just taught me how to make this work:
It's not necessary to have an <xsl:variable> for this case. Instead, I can embed the data document directly into the XSL stylesheet (putting it into a namespace for sanity) and then select elements from that. Here's the result:
<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:map="uri:map">
<xsl:output method="text" encoding="iso-8859-1"/>
<map:colors>
<entry><key>red</key><value>rot</value></entry>
<entry><key>green</key><value>gruen</value></entry>
<entry><key>blue</key><value>blau</value></entry>
</map:colors>
<xsl:template match="/">
<xsl:for-each select="document('')/*/map:colors/entry">
<xsl:value-of select="key"/>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
This generates the expected output redgreenblue.
The trick is to use document('') to get a handle to the XSLT document itself, then * to get into the toplevel xsl:stylesheet element and from there I can access the color map.

XSLT 2.0 External lookup using key() and document()

I'm pulling what's left of my hair out trying to get a simple external lookup working using Saxon 9.1.0.7.
I have a simple source file dummy.xml:
<something>
<monkey>
<genrecode>AAA</genrecode>
</monkey>
<monkey>
<genrecode>BBB</genrecode>
</monkey>
<monkey>
<genrecode>ZZZ</genrecode>
</monkey>
<monkey>
<genrecode>ZER</genrecode>
</monkey>
</something>
Then the lookup file is GenreSet_124.xml:
<GetGenreMappingObjectsResponse>
<tuple>
<old>
<GenreMapping DepartmentCode="AAA"
DepartmentName="AND - NEWS AND CURRENT AFFAIRS"
Genre="10 - NEWS"/>
</old>
</tuple>
<tuple>
<old>
<GenreMapping DepartmentCode="BBB"
DepartmentName="AND - NEWS AND CURRENT AFFAIRS"
Genre="11 - NEWS"/>
</old>
</tuple>
... lots more
</GetGenreMappingObjectsResponse>
What I'm trying to achieve is simply to get hold of the "Genre" value based on the "DepartmentCode" value.
So my XSL looks like:
...
<!-- Set up the genre lookup key -->
<xsl:key name="genre-lookup" match="GenreMapping" use="#DepartmentCode"/>
<xsl:variable name="lookupDoc" select="document('GenreSet_124.xml')"/>
<xsl:template match="/something">
<stuff>
<xsl:for-each select="monkey">
<Genre>
<xsl:apply-templates select="$lookupDoc">
<xsl:with-param name="curr-label" select="genrecode"/>
</xsl:apply-templates>
</Genre>
</xsl:for-each>
</stuff>
</xsl:template>
<xsl:template match="GetGenreMappingObjectsResponse">
<xsl:param name="curr-genrecode"/>
<xsl:value-of select="key('genre-lookup', $curr-genrecode)/#Genre"/>
</xsl:template>
...
The issue that I have is that I get nothing back. I currently just get
<?xml version="1.0" encoding="UTF-8"?>
<stuff>
<Genre/>
<Genre/>
<Genre/>
<Genre/>
</stuff>
I have moved all the lookup data to be attributes of GenreMapping, previously as child elements of GenreMapping whenever I entered the template match="GetGenreMappingObjectsResponse" it would just print out all text from every GenreMapping (DepartmentCode, DepartmentName, Genre)!
I can't for the life of me figure out what I am doing wrong. Any helpo/suggestions would be greatly appreciated.
PLease find the current actual XSLT listing:
<?xml version="1.0"?>
<xsl:stylesheet version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema">
<!-- Define the global parameters -->
<xsl:param name="TransformationID"/>
<xsl:param name="TransformationType"/>
<!-- Specify that XML is the desired output type -->
<xsl:output method="xml" encoding="UTF-8" indent="yes"/>
<!-- Set up the genre matching capability -->
<xsl:key name="genre-lookup" match="GenreMapping" use="#DepartmentCode"/>
<xsl:variable name="documentPath"><xsl:value-of select="concat('GenreSet_',$TransformationID,'.xml')"/></xsl:variable>
<xsl:variable name="lookupDoc" select="document($documentPath)"/>
<!-- Start the first match on the Root level -->
<xsl:template match="/something">
<stuff>
<xsl:for-each select="monkey">
<Genre>
<xsl:apply-templates select="$lookupDoc/*">
<xsl:with-param name="curr-genrecode" select="string(genrecode)"/>
</xsl:apply-templates>
</Genre>
</xsl:for-each>
</stuff>
</xsl:template >
<xsl:template match="GetGenreMappingObjectsResponse">
<xsl:param name="curr-genrecode"/>
<xsl:value-of select="key('genre-lookup', $curr-genrecode, $lookupDoc)/#Genre"/>
</xsl:template>
</xsl:stylesheet>
The TransformationID is alway 124 (so the correct lookup file is opened. The Type is just a name that I am currently not using but intending to.
In XSLT 2.0 there are two ways you can do what you want:
One is the three-parameter version of the key function. The third parameter lets you specify the root node you want the key to work on (by default it's always the root of the main document):
<xsl:value-of select="key('genre-lookup', $curr-genrecode,$lookupDoc)/#Genre"/>
Another way is to use the key function under the $lookupDoc node:
<xsl:value-of select="$lookupDoc/key('genre-lookup', $curr-genrecode)/#Genre"/>
Both of these methods are documented in the XSLT 2.0 specification on keys, and won't work in XSLT 1.0.
For the sake of completeness, you'd have to rewrite this to not use keys if you're restricted to XSLT 1.0.
<xsl:value-of select="$lookupDoc//GenreMapping[#DepartmentCode = $curr-genrecode]/#Genre"/>
Aha! The problem is the select="$lookupDoc" in your apply-templates call is calling a default template rather than the one you expect, so the parameter is getting lost.
Change it to this:
<xsl:apply-templates select="$lookupDoc/*">
<xsl:with-param name="curr-genrecode" select="string(genrecode)"/>
</xsl:apply-templates>
That will call your template properly and the key should work.
So the final XSLT sheet should look something like this:
<xsl:variable name="lookupDoc" select="document('XMLFile2.xml')"/>
<xsl:key name="genre-lookup" match="GenreMapping" use="#DepartmentCode"/>
<xsl:template match="/something">
<stuff>
<xsl:for-each select="monkey">
<Genre>
<xsl:apply-templates select="$lookupDoc/*">
<xsl:with-param name="curr-genrecode" select="string(genrecode)"/>
</xsl:apply-templates>
</Genre>
</xsl:for-each>
</stuff>
</xsl:template>
<xsl:template match="GetGenreMappingObjectsResponse">
<xsl:param name="curr-genrecode"/>
<xsl:value-of select="key('genre-lookup',$curr-genrecode,$lookupDoc)/#Genre"/>
</xsl:template>
OK, so this is a bit mental and I don't claim to understand it but it works (sounds like a career in software).
The issue I was having is that when I call the apply-templates and pass in the external document as a variable it never matched any templates even ones called "Genremapping".
So I used a wildcard to catch it, also when calling the apply-templates I narrowed down the node set to be the child I was interested in. This was pretty bonkers a I could print out the name of the node and see "GenreMapping" yet it never went into any template I had called "GenreMapping" choosing instead to only ever go to "*" template.
What this means is that my new template match gets called for every single GenreMapping node there is so it may be a little inefficient. What I realised then was all I needed to do was print sometihng out if a predicate matched.
So it looks like this now (no key used whatsoever):
...
<xsl:template match="/something">
<stuff>
<xsl:for-each select="monkey">
<Genre>
<key_value><xsl:value-of select="genrecode"/></key_value>
<xsl:variable name="key_val"><xsl:value-of select="genrecode"/></xsl:variable>
<code>
<xsl:apply-templates select="$lookupDoc/*/*/*/*">
<xsl:with-param name="curr-genrecode" select="string(genrecode)"/>
</xsl:apply-templates>
</code>
</Genre>
</xsl:for-each>
</stuff>
</xsl:template >
<xsl:template match="*">
<xsl:param name="curr-genrecode"/>
<xsl:value-of select=".[#DepartmentCode = $curr-genrecode]/#Genre"/>
</xsl:template>
...
All of which output:
Note, the last key_value correctly doesn't have a code entry as there is no match in the lookup document.
<?xml version="1.0" encoding="UTF-8"?>
<stuff xmlns:xs="http://www.w3.org/2001/XMLSchema">
<Genre>
<key_value>AAA</key_value>
<code>10 - NEWS</code>
</Genre>
<Genre>
<key_value>AAA</key_value>
<code>10 - NEWS</code>
</Genre>
<Genre>
<key_value>BBB</key_value>
<code>11 - NEWS</code>
</Genre>
<Genre>
<key_value>SVVS</key_value>
<code/>
</Genre>
</stuff>
Answer on a postcode. Thanks for the help Welbog.