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|
# class point :
int ->
object val mutable x : int method get_x : int method move : int -> unit end
# val p : point = <obj>
# - : int = 7
# - : unit = ()
# - : int = 10
# val q : < get_x : int; move : int -> unit > = <obj>
# - : int * int = (10, 17)
# class color_point :
int ->
string ->
object
val c : string
val mutable x : int
method color : string
method get_x : int
method move : int -> unit
end
# val p' : color_point = <obj>
# - : int * string = (5, "red")
# val l : point list = [<obj>; <obj>]
# val get_x : < get_x : 'a; .. > -> 'a = <fun>
# val set_x : < set_x : 'a; .. > -> 'a = <fun>
# - : int list = [10; 5]
# Characters 7-96:
......ref x_init = object
val mutable x = x_init
method get = x
method set y = x <- y
end..
Error: Some type variables are unbound in this type:
class ref :
'a ->
object
val mutable x : 'a
method get : 'a
method set : 'a -> unit
end
The method get has type 'a where 'a is unbound
# class ref :
int ->
object val mutable x : int method get : int method set : int -> unit end
# class ['a] ref :
'a -> object val mutable x : 'a method get : 'a method set : 'a -> unit end
# - : int = 2
# class ['a] circle :
'a ->
object
constraint 'a = < move : int -> unit; .. >
val mutable center : 'a
method center : 'a
method move : int -> unit
method set_center : 'a -> unit
end
# class ['a] circle :
'a ->
object
constraint 'a = #point
val mutable center : 'a
method center : 'a
method move : int -> unit
method set_center : 'a -> unit
end
# val c : point circle = <obj>
val c' : < color : string; get_x : int; move : int -> unit > circle = <obj>
# class ['a] color_circle :
'a ->
object
constraint 'a = #color_point
val mutable center : 'a
method center : 'a
method color : string
method move : int -> unit
method set_center : 'a -> unit
end
# Characters 28-29:
let c'' = new color_circle p;;
^
Error: This expression has type point but an expression was expected of type
#color_point
The first object type has no method color
# val c'' : color_point color_circle = <obj>
# - : color_point circle = <obj>
# Characters 0-21:
(c'' :> point circle);; (* Echec *)
^^^^^^^^^^^^^^^^^^^^^
Error: Type
color_point color_circle =
< center : color_point; color : string; move : int -> unit;
set_center : color_point -> unit >
is not a subtype of
point circle =
< center : point; move : int -> unit; set_center : point -> unit >
Type point is not a subtype of color_point
# Characters 9-55:
fun x -> (x : color_point color_circle :> point circle);;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: Type
color_point color_circle =
< center : color_point; color : string; move : int -> unit;
set_center : color_point -> unit >
is not a subtype of
point circle =
< center : point; move : int -> unit; set_center : point -> unit >
Type point is not a subtype of color_point
# class printable_point :
int ->
object
val mutable x : int
method get_x : int
method move : int -> unit
method print : unit
end
# val p : printable_point = <obj>
# 7- : unit = ()
# Characters 85-102:
inherit printable_point y as super
^^^^^^^^^^^^^^^^^
Warning 13: the following instance variables are overridden by the class printable_point :
x
The behaviour changed in ocaml 3.10 (previous behaviour was hiding.)
class printable_color_point :
int ->
string ->
object
val c : string
val mutable x : int
method color : string
method get_x : int
method move : int -> unit
method print : unit
end
# val p' : printable_color_point = <obj>
# (7, red)- : unit = ()
# class functional_point :
int ->
object ('a) val x : int method get_x : int method move : int -> 'a end
# val p : functional_point = <obj>
# - : int = 7
# - : int = 10
# - : int = 7
# - : #functional_point -> functional_point = <fun>
# class virtual ['a] lst :
unit ->
object
method virtual hd : 'a
method iter : ('a -> unit) -> unit
method map : ('a -> 'a) -> 'a lst
method virtual null : bool
method print : ('a -> unit) -> unit
method virtual tl : 'a lst
end
and ['a] nil :
unit ->
object
method hd : 'a
method iter : ('a -> unit) -> unit
method map : ('a -> 'a) -> 'a lst
method null : bool
method print : ('a -> unit) -> unit
method tl : 'a lst
end
and ['a] cons :
'a ->
'a lst ->
object
val h : 'a
val t : 'a lst
method hd : 'a
method iter : ('a -> unit) -> unit
method map : ('a -> 'a) -> 'a lst
method null : bool
method print : ('a -> unit) -> unit
method tl : 'a lst
end
# val l1 : int lst = <obj>
# (3::10::[])- : unit = ()
# val l2 : int lst = <obj>
# (4::11::[])- : unit = ()
# val map_list : ('a -> 'b) -> 'a lst -> 'b lst = <fun>
# val p1 : printable_color_point lst = <obj>
# ((3, red)::(10, red)::[])- : unit = ()
# class virtual comparable :
unit -> object ('a) method virtual leq : 'a -> bool end
# class int_comparable :
int -> object ('a) val x : int method leq : 'a -> bool method x : int end
# class int_comparable2 :
int ->
object ('a)
val x : int
val mutable x' : int
method leq : 'a -> bool
method set_x : int -> unit
method x : int
end
# class ['a] sorted_list :
unit ->
object
constraint 'a = #comparable
val mutable l : 'a list
method add : 'a -> unit
method hd : 'a
end
# val l : _#comparable sorted_list = <obj>
# val c : int_comparable = <obj>
# - : unit = ()
# val c2 : int_comparable2 = <obj>
# Characters 6-28:
l#add (c2 :> int_comparable);; (* Echec : 'a comp2 n'est un sous-type *)
^^^^^^^^^^^^^^^^^^^^^^
Error: Type
int_comparable2 =
< leq : int_comparable2 -> bool; set_x : int -> unit; x : int >
is not a subtype of
int_comparable = < leq : int_comparable -> bool; x : int >
Type int_comparable = < leq : int_comparable -> bool; x : int >
is not a subtype of
int_comparable2 =
< leq : int_comparable2 -> bool; set_x : int -> unit; x : int >
# - : unit = ()
# class int_comparable3 :
int ->
object
val mutable x : int
method leq : int_comparable -> bool
method setx : int -> unit
method x : int
end
# val c3 : int_comparable3 = <obj>
# - : unit = ()
# Characters 25-27:
(new sorted_list ())#add c3;; (* Error; strange message with -principal *)
^^
Error: This expression has type
int_comparable3 =
< leq : int_comparable -> bool; setx : int -> unit; x : int >
but an expression was expected of type
#comparable as 'a = < leq : 'a -> bool; .. >
Type int_comparable = < leq : int_comparable -> bool; x : int >
is not compatible with type 'a = < leq : 'a -> bool; .. >
The first object type has no method setx
# val sort : (#comparable as 'a) list -> 'a list = <fun>
# Characters 13-66:
List.map (fun c -> print_int c#x; print_string " ") l;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Warning 10: this expression should have type unit.
val pr : < x : int; .. > list -> unit = <fun>
# val l : int_comparable list = [<obj>; <obj>; <obj>]
# 5 2 4
- : unit = ()
# 2 4 5
- : unit = ()
# val l : int_comparable2 list = [<obj>; <obj>]
# 2 0
- : unit = ()
# 0 2
- : unit = ()
# val min : (#comparable as 'a) -> 'a -> 'a = <fun>
# - : int = 7
# - : int = 3
# class ['a] link :
'a ->
object ('b)
val mutable next : 'b option
val mutable x : 'a
method append : 'b option -> unit
method next : 'b option
method set_next : 'b option -> unit
method set_x : 'a -> unit
method x : 'a
end
# class ['a] double_link :
'a ->
object ('b)
val mutable next : 'b option
val mutable prev : 'b option
val mutable x : 'a
method append : 'b option -> unit
method next : 'b option
method prev : 'b option
method set_next : 'b option -> unit
method set_prev : 'b option -> unit
method set_x : 'a -> unit
method x : 'a
end
# val fold_right : ('a -> 'b -> 'b) -> 'a #link option -> 'b -> 'b = <fun>
# class calculator :
unit ->
object ('a)
val mutable acc : float
val mutable arg : float
val mutable equals : 'a -> float
method acc : float
method add : 'a
method arg : float
method enter : float -> 'a
method equals : float
method sub : 'a
end
# - : float = 5.
# - : float = 1.5
# - : float = 15.
# class calculator :
unit ->
object ('a)
val mutable acc : float
val mutable arg : float
val mutable equals : 'a -> float
method acc : float
method add : 'a
method arg : float
method enter : float -> 'a
method equals : float
method sub : 'a
end
# - : float = 5.
# - : float = 1.5
# - : float = 15.
# class calculator :
float ->
float ->
object
val acc : float
val arg : float
method add : calculator
method enter : float -> calculator
method equals : float
method sub : calculator
end
and calculator_add :
float ->
float ->
object
val acc : float
val arg : float
method add : calculator
method enter : float -> calculator
method equals : float
method sub : calculator
end
and calculator_sub :
float ->
float ->
object
val acc : float
val arg : float
method add : calculator
method enter : float -> calculator
method equals : float
method sub : calculator
end
# val calculator : calculator = <obj>
# - : float = 5.
# - : float = 1.5
# - : float = 15.
#
|
