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Request for Comments: A new n-ary function construction
Date: Wed, 22 Nov 89 11:55:42 PST
From: Pavel.pa@xerox.com
That is, you can now follow the ``required'' parameters by the marker
string "arbitrary" and two identifiers. The first of these will, on
invocation of the procedure, be bound to the number of ``extra'' arguments,
those not accounted for by the required parameters; it is an exact integer.
The second new identifier will be bound to a procedure of one argument, an
exact non-negative integer less than the extra argument count; it returns
the extra argument with that index.
I believe that it would be much cleaner to only use the second of the two extra
arguments. (i.e., the one which is bound to a procedure) The information
about the number of optional arguments which are supplied can be aquired
through the use of an arity function of the type previously discussed on the
rrrs-authors mailing list during a discussion on multiple values. I support
the arity approach because it is more general purpose and can be specified in a
manner that is orthoginal to the rest of Scheme. Why put in a special purpose
hack, when a more general solution is available.
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Morry Katz
katz@cs.stanford.edu
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