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From: davis@ilog.fr (Harley Davis)
Subject: Re: do-nothing macro generates nil nevertheless
In-Reply-To: vogt@netcom.com's message of Mon, 27 Feb 1995 05:21:02 GMT
Message-ID: <DAVIS.95Mar1180126@passy.ilog.fr>
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References: <3iqno7$mab@news.internex.net> <vogtD4n872.7Bt@netcom.com>
Date: 01 Mar 1995 17:01:26 GMT
Xref: glinda.oz.cs.cmu.edu comp.lang.lisp:16928 comp.lang.lisp.mcl:6500


In article <vogtD4n872.7Bt@netcom.com> vogt@netcom.com (Christopher J. Vogt) writes:

   >A macro's job is to return a list to be compiled.

   Try (listp nil).  It returns T, nil is a list.
   Try (length nil).  It returns 0, nil is a list of length 0.
   Try (values).  it doesn't return anything!  And I'll bet you
   thought that everything in lisp returns a value.  Hah!

Actually, several things in Lisp don't return a value.  For instance,
THROW, RETURN-FROM, and GO.

-- Harley
-- 

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