From: Eliot Handelman
Subject: Setf Method
Date: 
Message-ID: <3677@phoenix.Princeton.EDU>
I'm sorry, I didn't even state the problem right in my query. (Too much
terminal time.) What I meant was this:

A => (1 2 3)

(setf (last a) '()) and now a => (1 2). In effect I'm trying to pop the
last cons.

Obviously (rplaca (last a) nil) => (1 2 NIL)

and

(setq a (reverse (cdr (reverse a)))) or (setq a (butlast a))

only works for symbols. Is there some way to do it using rplaca or rplacd?
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From: Eliot Handelman
Subject: Re: Setf Method
Date: 
Message-ID: <3678@phoenix.Princeton.EDU>
Ignore my last two postings. I'd overlooked the primitive NBUTLAST. As
I say, disadvantages of late night work.
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