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From: krulwich@ils.nwu.edu (Bruce Krulwich)
Newsgroups: comp.lang.scheme
Subject: Re: How to redefine a procedure (extend it) and have nobody notice
Message-ID: <1347@anaxagoras.ils.nwu.edu>
Date: 12 Apr 91 15:25:22 GMT
References: <9104041549.AA16630@schizo>
Sender: news@ils.nwu.edu
Reply-To: krulwich@ils.nwu.edu (Bruce Krulwich)
Organization: Institute for the Learning Sciences, Northwestern University, Evanston, IL 60201
Lines: 22
In-reply-to: gjc@mitech.COM

In article <9104041549.AA16630@schizo>, gjc@mitech writes:
>What did prove useful to extending the calling conventions of
>a procedure was &KEY arguments.
...
>Did anyone ever propose the use of &KEY return values?
...
>p.s. I really think I *have* heard of somebody suggestion &KEY
>in multiple return values. I just cannot remember who or when.

It seems to me that this idea comes naturally if returning multiple values is
thought of as simply calling a continuation with more than one argument.  If
you're working in CL or another LISP with keyword arguments, why shouldn't
continuations have them just like all other procedures?

As a side note, in this view of multiple-value returns, the functions such as
RECEIVE-VALUES in T (and I suppose MULTIPLE-VALUE-CALL in CommonLISP) are
simply giving an explicit continuation to pass to another procedure.

Bruce Krulwich
krulwich@ils.nwu.edu