(defcc <expr>
  <term> <op> <expr> := [<op> <term> <expr>];
  <term> := <term>;)
  
(defcc <op>
  X := X  		where (element? X [+ - * /]);)
  
(defcc <term>
  N := N  where (number? N);
  E := (parse-term E);)
  
(define parse-term
  E -> (compile (fn <expr>) E))