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From: eliot@phoenix.Princeton.EDU (Eliot Handelman)
Newsgroups: comp.lang.lisp
Subject: Re: novice question
Message-ID: <3320@idunno.Princeton.EDU>
Date: 13 Oct 90 07:11:31 GMT
References: <90285.160549JEFHC@CUNYVM.BITNET> <raja.655772214@copper>
Sender: news@idunno.Princeton.EDU
Organization: Shitson University, New Crapsey
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In article <raja.655772214@copper> raja@copper.ucs.indiana.edu (Raja Sooriamurthi) writes:
;(defun snoc (l x) (append l (list x)))
;
;Mirror then becomes,
;
;(defun mirror (l)
;  (cond ((null l) nil)
;        ((listp l) (snoc (mirror (rest l))
;                         (mirror (first l))))
;        (t (snoc (mirror (rest l)) (first l)))))
;
;[I might have the syntax mixed up (listp - ?) as I usually program in
;Scheme, but you get the idea I presume]


You probably meant:

(defun mirror (l)
  (cond ((null l) nil)
	((listp l) (snoc (mirror (rest l)) (mirror (first l))))
	(t l)))