// The last character of the program is an extra closing parenthesis
data List a = Nil | Cons a (List a)

first Nil = 0
first (Cons x _) = x

reverse l = reverseAux Nil l 
  where
    reverseAux accum Nil = accum
    reverseAux accum (Cons h t) = reverseAux (Cons h accum) t    

main = first (reverse l) 
  where
    l = Cons 1 (Cons 2 (Cons 3 Nil)))
--
14:37-14:38: No corresponding opening parenthesis for ')'.