(defcc <asbas>
    <as> b <as>;)
 
(defcc <as>
        a <as>;    a;)

(compile (fn <asbas>) [a b a a a a a])

(defcc <asbas>
    <as> b <as+>;)

(defcc <as>
        a <as>;      a;)

(defcc <as+>
    <as>;)

(compile (fn <asbas>) [a b a a a a a])

(defcc <asbas>
    <as> <b> <as+>;)

(defcc <as>
        a <as>;
        a;)

(defcc <b>
   b;)

(defcc <as+>
    <as>;)
    
(compile (fn <asbas>) [a b a a a a a]) 

(defcc <b>
   b := b;)

(trap-error (compile (fn <asbas>) [a b a a a a a]) 
            (/. E (pr (error-to-string E))))

(defcc <asbas>
    <as> <b> <as+> := (append <as> [<b> | <as+>]);)

(compile (fn <asbas>) [a b a a a a a])