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Multiple values for R4RS.

	From: adams@tekchips.LABS.TEK.COM
	I would prefer not
	to be committed to keeping around arity information for every

    From: jinx@hpesogg.hp.COM
    You don't have to keep it around for every procedure.  

I know.  And this is a side issue.  I want multiple values, and I don't
want to get hung up on ACCEPTS?.

If you are interested in the side issue, here are my thoughts:

The requirement that some procedures support ACCEPTS? still imposes
constraints on the implementation.  You must have a representation of
procedures that can support ACCEPTS?  As an implementor, this is the
sort of language-imposed restriction I have found useful to eliminate.

    From: mkatz%sesame.stanford.edu
    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

Sure, it is present in some form.

Perhaps each procedure is responsible for coping with wrong number of
arguments passed in.  Somewhere in the procedure's code are
instructions that perform the check.  The information is there, but
with a sufficiently clever compiler -- the sort of implementation I
find most interesting -- finding that information could be
impractical, if not intractable.