Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!van-bc!ubc-cs!manis
From: manis@cs.ubc.ca (Vincent Manis)
Newsgroups: comp.lang.scheme
Subject: Re: (atom? '()) => #t
Message-ID: <7079@ubc-cs.UUCP>
Date: 8 Mar 90 03:20:13 GMT
References: <1990Mar7.194937.1421@sun.soe.clarkson.edu>
Sender: news@cs.ubc.ca
Reply-To: manis@cs.ubc.ca (Vincent Manis)
Organization: Bucky Bits Cereal Keyboards, Ltd.
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In article <1990Mar7.194937.1421@sun.soe.clarkson.edu>
jk0@sun.soe.clarkson.edu (Jason Coughlin) writes:

>Can someone explain the rationale behind treating '() as an atom?  It
>seems to me that it should be a pair:  it's the empty *list* not the
>empty *atom*.

But remember, a list isn't a pair. It's zero or more pairs connected
together via a cdr chain. In fact, a pair is an object to which the car
and cdr procedures may be applied; it has been considered unkosher for
many years to allow (car '()) and (cdr '()).


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