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Re: do-nothing macro generates nil nevertheless
- To: info-mcl@digitool.com
- Subject: Re: do-nothing macro generates nil nevertheless
- From: davis@ilog.fr (Harley Davis)
- Date: 01 Mar 1995 17:01:26 GMT
- Organization: Ilog SA, Gentilly, France
- References: <3iqno7$mab@news.internex.net>, <vogtD4n872.7Bt@netcom.com>
- Sender: owner-info-mcl@digitool.com
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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