Path: utzoo!mnetor!uunet!husc6!mailrus!ames!necntc!ima!haddock!karl
From: karl@haddock.ISC.COM (Karl Heuer)
Newsgroups: comp.lang.misc
Subject: multiple values
Message-ID: <3213@haddock.ISC.COM>
Date: 29 Mar 88 18:18:04 GMT
References: <12176@brl-adm.ARPA> <1988Mar11.215238.976@utzoo.uucp> <3177@haddock.ISC.COM> <727@l.cc.purdue.edu>
Reply-To: karl@haddock.ima.isc.com (Karl Heuer)
Organization: Interactive Systems, Boston
Lines: 27

In article <727@l.cc.purdue.edu> cik@l.cc.purdue.edu (Herman Rubin) writes:
>In article <3177@haddock.ISC.COM>, karl@haddock.ISC.COM (Karl Heuer) writes:
>>   (setq z
>>         ((lambda (qr) (+ (* (car qr) (car qr)) (* (cdr qr) (cdr qr))))
>>          (div x y)))
>
>In Lisp, the language certainly suggests that at some time there is a real
>machine object called qr.  The way I am proposing the list, this is never
>more than a virtual object, and does not need a name.  However, the user
>assigns names to the elements of the list, and refers to them, rather than
>having to write (car qr) and (cdr qr).

So?  The way I wrote it, q and r are never more than unnamed virtual objects.
I'm looking for a syntax that allows all three (qr, q, r) to disappear, if
all I really want is an expression that returns q*q+r*r.  If we allow 2-d
notation, this could be written

                      +---+
         +---+    /-->| * |
     x-->|   |---+--->|   |---\    +---+
         |div|        +---+    --->| + |--->z
     y-->|   |--\     +---+    --->|   |
         +---+   +--->| * |---/    +---+
                  \-->|   |
                      +---+

Karl W. Z. Heuer (ima!haddock!karl or karl@haddock.isc.com), The Walking Lint