Macro for division and reciprocal
See binary-* for multiplication and see unary-/ for reciprocal.
(/ x y)
represents the same term as
(* x (/ y))
which is really
(binary-* x (unary-/ y)).
Also note that
(defmacro / (x &optional (y 'nil binary-casep)) (cond (binary-casep (list 'binary-* x (list 'unary-/ y))) (t (list 'unary-/ x))))