Use of variables in location paths

In response to an ancient posting from Jon Smirl (later reproduced in
the FAQ document), Ken Holman once wrote:

   "If the variable isn't a node set, then it cannot be used directly
   as a location step in a location path."

I can see from the behavior of every XSL/T process that I have tried
this this is clearly true.  My question is, how would I have been able
to come to this conclusion solely from reading the language in the W3C
recommendations?  Can anyone point me to the specific passages which
make it clear that node set variables can be used in a location path but
string variables cannot?

Thanks very much!

-- 
Bob Kline
mailto:bkline@xxxxxxxxxxxxx
http://www.rksystems.com



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