# Characters 12-32:
  type 'a t = [`A of 'a t t] as 'a;; (* fails *)
              ^^^^^^^^^^^^^^^^^^^^
Error: Constraints are not satisfied in this type.
       Type
       [ `A of 'a ] t t as 'a
       should be an instance of
       ([ `A of 'b t t ] as 'b) t
#   Characters 5-27:
  type 'a t = [`A of 'a t t];; (* fails *)
      ^^^^^^^^^^^^^^^^^^^^^^
Error: In the definition of t, type 'a t t should be 'a t
#   type 'a t = [ `A of 'a t t ] constraint 'a = 'a t
#   type 'a t = [ `A of 'a t ] constraint 'a = 'a t
#   type 'a t = 'a constraint 'a = [ `A of 'a ]
#   Characters 47-52:
  type 'a v = [`A of u v] constraint 'a = t and t = u and u = t;; (* fails *)
                                                ^^^^^
Error: The type abbreviation t is cyclic
#   type 'a t = 'a
# Characters 11-21:
  let f (x : 'a t as 'a) = ();; (* fails *)
             ^^^^^^^^^^
Error: This alias is bound to type 'a t = 'a
       but is used as an instance of type 'a
       The type variable 'a occurs inside 'a
#   val f : 'a t -> 'a -> bool = <fun>
#               Characters 83-122:
    and 'o abs constraint 'o = 'o is_an_object
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: The definition of abs contains a cycle:
       'a is_an_object as 'a
#