#   - : < x : int > ->
    < x : int > -> < x : int > -> < x : int > * < x : int > * < x : int >
= <fun>
#               class ['a] c : unit -> object constraint 'a = int method f : int c end
and ['a] d : unit -> object constraint 'a = int method f : int c end
#                 Characters 230-271:
  ....and d () = object
    inherit ['a] c ()
  end..
Error: Some type variables are unbound in this type:
         class d : unit -> object method f : 'a -> unit end
       The method f has type 'a -> unit where 'a is unbound
#             class virtual c : unit -> object  end
and ['a] d :
  unit -> object constraint 'a = < x : int; .. > method f : 'a -> int end
#                 class ['a] c : unit -> object constraint 'a = int end
and ['a] d : unit -> object constraint 'a = int #c end
# *             class ['a] c :
  'a -> object ('a) constraint 'a = < f : 'a; .. > method f : 'a end
# - : ('a c as 'a) -> 'a = <fun>
# *           Characters 128-176:
  class x () = object
    method virtual f : int
  end..
Error: This class should be virtual. The following methods are undefined : f
#               Characters 144-152:
  class virtual c ((x : 'a): < f : int >) = object (_ : 'a) end
                                                   ^^^^^^^^
Error: This pattern cannot match self: it only matches values of type
       < f : int >
#           Characters 32-110:
  class ['a] c () = object
    constraint 'a = int
    method f x = (x : bool c)
  end..
Error: The abbreviation c is used with parameters bool c
       which are incompatible with constraints int c
#             class ['a, 'b] c :
  unit ->
  object
    constraint 'a = int -> 'c
    constraint 'b = 'a * < x : 'b > * 'c * 'd
    method f : 'a -> 'b -> unit
  end
#     class ['a, 'b] d :
  unit ->
  object
    constraint 'a = int -> 'c
    constraint 'b = 'a * < x : 'b > * 'c * 'd
    method f : 'a -> 'b -> unit
  end
#     val x : '_weak1 list ref = {contents = []}
#     Characters 0-50:
  class ['a] c () = object
    method f = (x : 'a)
  end..
Error: The type of this class,
       class ['a] c :
         unit -> object constraint 'a = '_weak1 list ref method f : 'a end,
       contains type variables that cannot be generalized
#       Characters 21-53:
  type 'a c = <f : 'a c; g : 'a d>
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: In the definition of d, type int c should be 'a c
#   type 'a c = < f : 'a c; g : 'a d >
and 'a d = < f : 'a c >
#   type 'a c = < f : 'a c >
and 'a d = < f : int c >
#   Characters 22-39:
  and 'a t = 'a t u;; (* fails since 4.04 *)
  ^^^^^^^^^^^^^^^^^
Error: The definition of t contains a cycle:
       'a t u
#   Characters 15-32:
  and 'a t = 'a t u;;
  ^^^^^^^^^^^^^^^^^
Error: The type abbreviation t is cyclic
# type 'a u = 'a
# Characters 0-18:
  type t = t u * t u;;
  ^^^^^^^^^^^^^^^^^^
Error: The type abbreviation t is cyclic
#   type t = < x : 'a > as 'a
# type 'a u = 'a
# - : t -> t u -> bool = <fun>
# - : t -> t u -> bool = <fun>
#                         module M :
  sig
    class ['a, 'b] c :
      int ->
      'b ->
      object
        constraint 'a = int -> bool
        val x : float list
        val y : 'b
        method f : 'a -> unit
        method g : 'b
      end
  end
#                   module M' :
  sig
    class virtual ['a, 'b] c :
      int ->
      'b ->
      object
        constraint 'a = int -> bool
        val x : float list
        val y : 'b
        method f : 'a -> unit
        method g : 'b
      end
  end
# class ['a, 'b] d :
  unit ->
  'b ->
  object
    constraint 'a = int -> bool
    val x : float list
    val y : 'b
    method f : 'a -> unit
    method g : 'b
  end
# class ['a, 'b] e :
  unit ->
  'b ->
  object
    constraint 'a = int -> bool
    val x : float list
    val y : 'b
    method f : 'a -> unit
    method g : 'b
  end
# - : string = "a"
# - : int = 10
# - : float = 7.1
# # - : bool = true
#     module M : sig class ['a] c : unit -> object method f : 'a -> unit end end
#   module M' : sig class ['a] c : unit -> object method f : 'a -> unit end end
# - : ('a #M.c as 'b) -> 'b = <fun>
# - : ('a #M'.c as 'b) -> 'b = <fun>
# class ['a] c : 'a #c -> object  end
# class ['a] c : 'a #c -> object  end
#     class c : unit -> object method f : int end
and d : unit -> object method f : int end
# class e : unit -> object method f : int end
# - : int = 2
# Characters 30-34:
  class c () = object val x = - true val y = -. () end;;
                                ^^^^
Error: This expression has type bool but an expression was expected of type
         int
#   class c : unit -> object method f : int method g : int method h : int end
# class d : unit -> object method h : int method i : int method j : int end
#               class e :
  unit ->
  object
    method f : int
    method g : int
    method h : int
    method i : int
    method j : int
  end
# val e : e = <obj>
# - : int * int * int * int * int = (1, 3, 2, 2, 3)
#   class c : 'a -> object val a : 'a val x : int val y : int val z : int end
# class d : 'a -> object val b : 'a val t : int val u : int val z : int end
#                             Characters 42-45:
    inherit c 5
            ^^^
Warning 13: the following instance variables are overridden by the class c :
  x
The behaviour changed in ocaml 3.10 (previous behaviour was hiding.)
Characters 52-53:
    val y = 3
        ^
Warning 13: the instance variable y is overridden.
The behaviour changed in ocaml 3.10 (previous behaviour was hiding.)
Characters 80-83:
    inherit d 7
            ^^^
Warning 13: the following instance variables are overridden by the class d :
  t z
The behaviour changed in ocaml 3.10 (previous behaviour was hiding.)
Characters 90-91:
    val u = 3
        ^
Warning 13: the instance variable u is overridden.
The behaviour changed in ocaml 3.10 (previous behaviour was hiding.)
class e :
  unit ->
  object
    val a : int
    val b : int
    val t : int
    val u : int
    val x : int
    val y : int
    val z : int
    method a : int
    method b : int
    method t : int
    method u : int
    method x : int
    method y : int
    method z : int
  end
# val e : e = <obj>
# - : int * int * int * int * int * int * int = (1, 3, 2, 2, 3, 5, 7)
#             class c :
  int ->
  int -> object val x : int val y : int method x : int method y : int end
# class d :
  int ->
  int -> object val x : int val y : int method x : int method y : int end
# - : int * int = (1, 2)
# - : int * int = (1, 2)
#     class ['a] c : 'a -> object  end
# - : 'a -> 'a c = <fun>
#     * * * * * * * * * * * * * * * * * * * * *                             module M : sig class c : unit -> object method xc : int end end
#         class d : unit -> object val x : int method xc : int method xd : int end
# - : int * int = (1, 2)
#         Characters 1-154:
  class virtual ['a] matrix (sz, init : int * 'a) = object
    val m = Array.make_matrix sz sz init
    method add (mtx : 'a matrix) = (mtx#m.(0).(0) : 'a)
  end..
Error: The abbreviation 'a matrix expands to type < add : 'a matrix -> 'a >
       but is used with type < m : 'a array array; .. >
#   class c : unit -> object method m : c end
# - : c = <obj>
# module M : sig class c : unit -> object method m : c end end
# - : M.c = <obj>
#   type uu = A of int | B of (< leq : 'a > as 'a)
#   class virtual c : unit -> object ('a) method virtual m : 'a end
#         module S : sig val f : (#c as 'a) -> 'a end
#         Characters 12-43:
  ............struct
    let f (x : #c) = x
  end......
Error: Signature mismatch:
       Modules do not match:
         sig val f : (#c as 'a) -> 'a end
       is not included in
         sig val f : #c -> #c end
       Values do not match:
         val f : (#c as 'a) -> 'a
       is not included in
         val f : #c -> #c
#   Characters 38-39:
  module M = struct type t = int class t () = object end end;;
                                       ^
Error: Multiple definition of the type name t.
       Names must be unique in a given structure or signature.
#   - : < m : (< m : 'a > as 'b) -> 'b as 'a; .. > -> 'b = <fun>
#   Characters 10-39:
  fun x -> (x : int -> bool :> 'a -> 'a);;
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: Type int -> bool is not a subtype of int -> int 
       Type bool is not a subtype of int 
# Characters 9-40:
  fun x -> (x : int -> bool :> int -> int);;
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: Type int -> bool is not a subtype of int -> int 
       Type bool is not a subtype of int 
# - : <  > -> <  > = <fun>
# - : < .. > -> <  > = <fun>
#   val x : '_weak2 list ref = {contents = []}
#   module F : functor (X : sig  end) -> sig type t = int end
# - : < m : int > list ref = {contents = []}
#   type 'a t
# Characters 9-19:
  fun (x : 'a t as 'a) -> ();;
           ^^^^^^^^^^
Error: This alias is bound to type 'a t but is used as an instance of type 'a
       The type variable 'a occurs inside 'a t
# Characters 19-20:
  fun (x : 'a t) -> (x : 'a); ();;
                     ^
Error: This expression has type 'a t but an expression was expected of type
         'a
       The type variable 'a occurs inside 'a t
# type 'a t = < x : 'a >
# - : ('a t as 'a) -> unit = <fun>
# Characters 18-26:
  fun (x : 'a t) -> (x : 'a); ();;
                    ^^^^^^^^
Warning 10: this expression should have type unit.
- : ('a t as 'a) t -> unit = <fun>
#         class ['a] c :
  unit ->
  object constraint 'a = (< .. > as 'b) -> unit method m : 'b -> unit end
#       class ['a] c :
  unit ->
  object constraint 'a = unit -> (< .. > as 'b) method m : 'a -> 'b end
#         class c : unit -> object method private m : int method n : int end
#         class d :
  unit -> object method private m : int method n : int method o : int end
#   - : int * int = (1, 1)
#   class c : unit -> object method m : int end
#       val r : int ref = {contents = 0}
# val id : < .. > -> int = <fun>
# - : unit = ()
# - : int = 1
# - : int = 2
#         - : int * int * int = (3, 4, 5)
#           - : int * int * int * int * int = (6, 7, 8, 33, 33)
#           - : int * int * int * int * int * int * int = (9, 10, 10, 11, 11, 33, 33)
#         Characters 42-69:
  class a = let _ = new b in object end
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: This kind of recursive class expression is not allowed
#   Characters 11-38:
  class a = let _ = new a in object end;;
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: This kind of recursive class expression is not allowed
#