Single transformation using XSLT on-the-fly

Using a *single* transformation, is there a way to create an XSLT 2.0
on-the-fly and apply it to a document? I tried many different ways, but
I think that's impossible because, even if I can save the XSLT in a
document (xsl:result-document), I can't include it at run-time.

Thanks, Giacomo.