File "t05bad.ml", line 10, characters 0-75:
10 | module rec A : sig type t = B.t -> int end = struct type t = B.t -> int end
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: The definition of "A.t" contains a cycle:
         "B.t -> int" contains "B.t",
         "B.t" = "A.t",
         "A.t" = "B.t -> int",
         "B.t -> int" contains "B.t",
         "B.t" = "A.t"