Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!ephemeral.ai.toronto.edu!bradb
From: bradb@ai.utoronto.ca
Newsgroups: comp.lang.lisp
Subject: Simple question RE nested DEFUNs
Message-ID: <89Jul31.114325edt.11243@ephemeral.ai.toronto.edu>
Date: 31 Jul 89 15:44:12 GMT
Expires: Aug 31 1989
Reply-To: bradb@ai.utoronto.ca
Followup-To: comp.lang.lisp
Organization: Department of Computer Science, University of Toronto
Lines: 25

I come from a Scheme background, where I'm used to defining helping
functions within the body of the function being helped, as in

	(define (foo a)

	  (define (bar b)
	    (... do some stuff with b and return result ...))

	  (... do some stuff with a and call bar as a ...)
	  (... helping function ...))

Now, when I do this in CommonLisp, I notice that the inner DEFUN
(the one for bar in my example) is actually being re-defined on
every invocation of foo.  Eek, this is not what I wanted!  I wanted
the function to be defined exactly once, before foo is ever called,
but available only within the scope of the definition of foo.

I'm sure there is a proper way to do this in CommonLisp, but I'm
not sure what it is.  Could some kind soul please enlighten me?

Thanks very much in advance,
					(-:  Brad Brown  :-)
					bradb@ai.utoronto.ca

(I knew there was a reason I liked Scheme and all it's simplicity...)