Parameterized entities?

Hi Folks,

Is there any way to express a parameterized ENTITY?

Example: I'd like to write something like this:

<!DOCTYPE xsl:stylesheet [
<!ENTITY file(f) "<xsl:variable name=f select='doc(f)'/>">
]>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    &file('ARPT.XML');
    &file('NAV.XML');
    &file('TRM.XML');
</xsl:stylesheet>

And have the XML parser perform the entity substitutions to generate this:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:variable name='ARPT.XML' select="doc('ARPT.XML')"/>
    <xsl:variable name='NAV.XML' select="doc('NAV.XML')"/>
    <xsl:variable name='TRM.XML' select="doc('TRM.XML')"/>
</xsl:stylesheet>

Is there any way to do something like this? 

/Roger