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From: gunter@netcom9.netcom.com (Michial A. Gunter)
Subject: A proposal for #f and '() in the GNU extension language
Message-ID: <GUNTER.94Oct25171012@netcom9.netcom.com>
Sender: gunter@netcom.com (Michial A. Gunter)
Organization: NETCOM On-line services
Date: Wed, 26 Oct 1994 00:10:11 GMT
Lines: 25


(I don't claim to know much about Scheme, Emacs Lisp, or GNU's plans
with respect to an extension language.)

Let's suppose that the reason the #f and '() will be the same in the
GNU extension language is that this is the way Emacs Lisp treats the
false value and the empty list.  (Is this supposition valid?)

Let's also assume that GNU's goals can be met by providing a front-end
for Emacs Lisp.  Then it seems that the front-end for the Emacs Lisp
syntax could change all accurances of #f and '() to a new value
#f-or-empty-list.  All of the Emacs Lisp primitives could return the
appropriate results when given #f-or-empty-list and there would be no
need to tamper with Scheem's distinction between #f and '().  However,
when calling Scheme from Emacs Lisp something would have to be done
with $f-or-empty-list.

Comments?

	mike gunter





