XSLT Xalan dyn:evaluate example

I want yo use the EXSLT - DYN:EVALUATE in a style sheet. I have added the names pace but I don't know where the .xsl file I need to import is. I don't believe I have XALAN installed to point the import to. How would I install this? Once installed and I point it to the .xsl will it pick up the function and apply it? I am running Windows. The XSLT file is included at the top of the XML document.

Thanks

Pete

Solution

Xalan has the EXSL dyn:evaluate function built-in, you don't need to import anything in order to use it. You just need to declare the namespace. I'll give a small example:

input.xml:

<root>
<foo>I am foo</foo>    
<bar>I am bar</bar>    
</root>

dyn_evaluate.xsl:

<xsl:stylesheet version="1.0"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
    xmlns:dyn="http://exslt.org/dynamic"
    extension-element-prefixes="dyn">

  <xsl:param name="path"/>

  <xsl:output method="text"/>

  <xsl:template match="/">
    <xsl:value-of select="dyn:evaluate($path)"/>
  </xsl:template>

</xsl:stylesheet>

Running

xalan.exe -p path '/root/foo' input.xml dyn_evaluate.xsl

gives

I am foo

Running

xalan.exe -p path '/root/bar' input.xml dyn_evaluate.xsl

gives

I am bar

Hope this helps.