Plaster

* (setf a '(1 2 3)) (1 2 3) * (pop (cdr a)) 2 * a (1 3) * (setf a '(1 2 3)) (1 2 3) * (setf b (cdr a)) (2 3) * (pop b) 2 * b (3) * a (1 2 3)