You can access Java system properties in the system-property() function

<xsl:include use-when="system-property('java.user')='mike'" href="..."/>

This is of course implementation-defined.

Michael Kay
http://www.saxonica.com/ 

> -----Original Message-----
> From: Vladimir Nesterovsky [mailto:vladimir@xxxxxxxxxxxxxxxxxxxx] 
> Sent: 28 August 2008 15:48
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject:  use-when in the xsl:inlcude
> 
> Hell,
> 
> Is there something I can pass to xslt for it to evaluate that 
> something in the use-when attribute in the xsl:inlcude, and 
> xsl:import?
> 
> In particular I'm using saxon in java.
> 
> P.S. I almost certain that the answer is no, but who knows.
> 
> P.P.S. The only way I have found is though an extension 
> function, unfortunately stateless, thus useless, unless I use 
> thread statics.
> 
> Thanks.
> --
> Vladimir Nesterovsky
> http://www.nesterovsky-bros.com