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An alternate description of the multiple values proposal

   Date: Fri, 01 Sep 89 10:40:57 PDT
   From: Pavel.pa@xerox.com

   I have a disagreement with Will's description of the consensus.  He says,
   ``Except for continuations created by the procedure to be named later, all
   continuations take exactly one value, as now''.  I firmly believe that
   continuations for the ``for effect'' context should take any number of
   arguments; I would very much not like to see this left unspecified.

I'm not sure I agree with this definition of "for effect"
continuations.  I do agree that they should be required to accept
either zero arguments (because that is the "correct" arity for a
strict semantics) or one argument (for compatibility with existing
code).  However, I see no compelling reason why such continuations
should be required to accept more than one argument.  I would prefer
to leave this unspecified, because I believe it is an exact parallel
with the case of "for value" implicit continuations accepting more
than one argument.

(I can imagine that if I were considering the design of a new
language, I might choose a strict semantics in which "for effect"
implicit continuations accepted -only- zero arguments, and "for value"
implicit continuations accepted -only- one argument.  There is a
simple elegance in such a design that I find appealing.)