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Multiple values for R4RS.



   Date: Tue, 22 Aug 89 15:34:50 PDT
   From: Morris Katz <mkatz%sesame.stanford.edu@relay.cs.net>

      Date: Tue, 22 Aug 89 14:15:28 PDT
      From: Norman Adams <adams%tekchips.labs.tek.com@relay.cs.net>

      As an implementor, I would prefer not
      to be committed to keeping around arity information for every
      procedure.

   I can't imagine how one could create an implementation in which the arity
   information is not already present in some form for procedures that are passed
   as arguments.  Similarly, implicit continuations had better know something
   about the number of values on which they intend to operate.  Retrieving the
   arity information may require some bit twiddling, but I suspect that the needed
   information is always present in some form.

You could always walk down the machine language code, trying to figure
out which registers or stack slots it is touching in order to fetch arguments.
(This is not a claim of good engineering, just an existence proof.)
--Guy