xslt keep multiple variables in scope depending on a single test - xslt

Question

I have many variables and only two cases.
My original approach goes out of scope:
<xsl:choose>
<xsl:when test='$something = 6'>
<xsl:variable name="foo">x</xsl:variable>
<!-- 50 other variables -->
</xsl:when>
<xsl:when test='$something = 7'>
<xsl:variable name="foo">y</xsl:variable>
<!-- 50 other variables -->
</xsl:when>
</xsl:choose>
ie. later, with saxon, XPST0008: Variable x has not been declared (or its declaration is not in scope)
I think it would work if I would choose inside an xsl:variable tag, but then the tests would be repeated over and over and over and over and over:
<xsl:variable name="foo">
<xsl:choose>
<xsl:when test='$something = 6'>x</xsl:when>
<xsl:when test='$something = 7'>y</xsl:when>
</xsl:choose>
</xsl:variable>
<!-- 50 other variables, the two tests repeated for each... -->
Is there a way to keep the variables in scope but also don't repeat myself?
update 1
adding the complete 'sscce' files on request
original approach:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<xsl:variable name="something">6</xsl:variable>
<xsl:choose>
<xsl:when test="$something = '6'">
<xsl:variable name="foo">x</xsl:variable>
<!-- 50 other variables -->
</xsl:when>
<xsl:when test="$something = '7'">
<xsl:variable name="foo">y</xsl:variable>
<!-- 50 other variables -->
</xsl:when>
</xsl:choose>
<xsl:value-of select="$foo"/>
</xsl:template>
</xsl:stylesheet>
approach that works but forces to repeat myself:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<xsl:variable name="something">6</xsl:variable>
<xsl:variable name="foo">
<xsl:choose>
<xsl:when test='$something = 6'>x</xsl:when>
<xsl:when test='$something = 7'>y</xsl:when>
</xsl:choose>
</xsl:variable>
<!-- 50 other variables, the two tests repeated for each... -->
<xsl:value-of select="$foo"/>
</xsl:template>
</xsl:stylesheet>
example xml file: <xml/>. example saxon command-line: java -jar saxon9he.jar -s:in.xml -xsl:in.xsl -o:out.html

Answer 1

Well, I'd rather process that way :
<xsl:variable name="something">6</xsl:variable>
<xsl:variable name="var.set">
<xsl:choose>
<xsl:when test="$something = '6'">
<foo>x</foo>
<bar>xx</bar>
<!-- 50 other variables, to be inserted as tag -->
</xsl:when>
<xsl:when test="$something = '7'">
<foo>y</foo>
<bar>yy</bar>
<!-- 50 other variables, to be inserted as tag -->
</xsl:when>
</xsl:choose>
</xsl:variable>
The variable var.set will be a nodeset that you will be able to read thanks to the exsl:node-set() extension.
For example to retrieve the value for foo (stored as a node and not as a variable anymore), use something like: <xsl:value-of select="exsl:node-set($var.set)/foo" />. Like this you will handle a single variable, quite as if it were an array of values.
PS: on the root tag of your stylesheet, do not forget to add the exsl namespace declaration xmlns:exsl="http://exslt.org/common" extension-element-prefixes="exsl"

Answer 2

If you know your mappings beforehand, you can store them in their own file.
So instead of having something like this
<xsl:variable name="var1">
<xsl:if test="something = 5">x</xsl:if>
</xsl:variable>
<xsl:value-of select="$var1"/>
You could have this
<xsl:value-of select="document('other.xml')/root/scheme[#number = 5]/#value"/>
With this as other.xml
<root>
<scheme number="5" value="x"/>
<scheme number="6" value="y"/>
</root>
You'll probably want a more complex other.xml, with various groups of colours for each colour scheme, but the idea would be the same, and avoids tests and variables completely.