すいません。

[第2回]

p15. | hd :: tl = f hd :: map f tl;;
 →  | hd :: tl -> f hd :: map f tl;;

p19. let add_comp {re=r1; im=i1} {re=r2; im=i2} = {re = r1+r2; im=i1+i2};;
  → let add_comp {re=r1; im=i1} {re=r2; im=i2} = {re = r1+.r2; im=i1+.i2};;

p35. filter f x = foldr (...) [] y
  → filter f x = foldr (...) [] x


[第3回]

p14. val a = ref 0
  → let a = ref 0


[第4回]

p8. let (x, y) as pair = (ref 1, ref 2) in x (fst pair)
 → let (x, y) as pair = (ref 1, ref 2) in test x (fst pair)

p12. val prod : int list -> list
 →  val prod : int list -> int


あと、サンプルソースの MultiSet の削除周りの実装が派手にバグってました。

[第6回]

p12. let rec loop x = loop x in fst (5, iter x) → fst (5, iter x) ………
 →  let rec loop x = loop x in fst (5 + 3, loop x) → fst (5 + 3, loop x) ………