Re: (atom? '()) => #t

[Vincent Manis <van-bc!ubc-cs!manis@uunet.uu.net>]

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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