Re: [Chicken-users] The predicate "atom?" considered bizarre

[felix winkelmann]

On 8/31/06, John Cowan <address@hidden> wrote:
> While messing around with some stuff in Paul Graham's paper "The Roots
> of Lisp" I was quite surprised to find that Chicken's "atom?" predicate
> returns #f on the empty list.  This is the documented behavior.
>
> This is contrary to historic practice from Lisp 1.5 through Common Lisp.
> (Of course that is partly because () = NIL in that tradition, and NIL
> is a symbol.)  R1RS was the last Scheme standard to specify ATOM, and
> it had the same semantics then.
>
> Why was this changed?  Can it be fixed?

I have changes this. Note that "atom?" is now equivalent to
"not-pair?".


cheers,
felix

--
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