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|
(* TEST
expect;
*)
class virtual child1 parent =
object
method private parent = parent
end
and virtual child2 =
object(_ : 'self)
constraint 'parent = < previous: 'self option; .. >
method private virtual parent: 'parent
end
[%%expect{|
class virtual child1 : 'a -> object method private parent : 'a end
and virtual child2 :
object ('a)
method private virtual parent : < previous : 'a option; .. >
end
|}]
class virtual child1' parent =
object
method private parent = parent
end
and virtual child2' =
object(_ : 'self)
constraint 'parent = < previous: 'self option; .. >
method private virtual parent: 'parent
end
and foo = object(self)
method previous = None
method child =
object
inherit child1' self
inherit child2'
end
end;;
[%%expect{|
Line 16, characters 22-26:
16 | inherit child1' self
^^^^
Error: The value "self" has type "< child : 'a; previous : 'b option; .. >"
but an expression was expected of type "'c"
Self type cannot escape its class
|}]
(* Whether we have [class foo1] or [let foo1] doesn't change a thing. *)
class foo1 = object(self)
method previous = None
method child =
object
inherit child1 self
inherit child2
end
end;;
[%%expect{|
class foo1 : object method child : child1 method previous : child1 option end
|}]
class nested = object
method obj = object(self)
method previous = None
method child () =
object
inherit child1 self
inherit child2
end
end
end;;
[%%expect{|
class nested :
object
method obj : < child : unit -> child1; previous : child1 option >
end
|}]
class just_to_see = object(self)
method previous = None
method child =
let o =
object
inherit child1 self
inherit child2
end
in
o
end;;
[%%expect{|
class just_to_see :
object method child : child1 method previous : child1 option end
|}]
class just_to_see2 = object
method obj = object(self)
method previous = None
method child =
let o =
object
inherit child1 self
inherit child2
end
in
o
end
end;;
[%%expect{|
class just_to_see2 :
object method obj : < child : child1; previous : child1 option > end
|}]
type gadt = Not_really_though : gadt
class just_to_see3 = object(self)
method previous = None
method child Not_really_though =
object
inherit child1 self
inherit child2
end
end;;
[%%expect{|
type gadt = Not_really_though : gadt
class just_to_see3 :
object method child : gadt -> child1 method previous : child1 option end
|}]
class leading_up_to = object(self : 'a)
method previous : 'a option = None
method child =
object
inherit child1 self
inherit child2
end
end;;
[%%expect{|
Lines 4-7, characters 4-7:
4 | ....object
5 | inherit child1 self
6 | inherit child2
7 | end
Error: This object has undeclared virtual methods.
The following methods were not declared : "previous" "child"
|}]
class assertion_failure = object(self : 'a)
method previous : 'a option = None
method child =
object
inherit child1 self
inherit child2
method previous = None
method child = assert false
end
end;;
[%%expect{|
Lines 4-10, characters 4-7:
4 | ....object
5 | inherit child1 self
6 | inherit child2
7 |
8 | method previous = None
9 | method child = assert false
10 | end
Error: Cannot close type of object literal:
"< child : '_weak2; previous : '_weak1 option; .. > as '_weak1"
it has been unified with the self type of a class that is not yet
completely defined.
|}]
(* MPR#7894 and variations *)
class parameter_contains_self app = object(self)
method invalidate : unit =
app#redrawWidget self
end;;
[%%expect{|
class parameter_contains_self :
< redrawWidget : 'a -> unit; .. > ->
object ('a) method invalidate : unit end
|}]
class closes_via_inheritance param =
let _ = new parameter_contains_self param in object
inherit parameter_contains_self param
end;;
[%%expect{|
Line 3, characters 36-41:
3 | inherit parameter_contains_self param
^^^^^
Error: The value "param" has type
"< redrawWidget : parameter_contains_self -> unit; .. >"
but an expression was expected of type
"< redrawWidget : < invalidate : unit; .. > -> unit; .. >"
Type "parameter_contains_self" = "< invalidate : unit >"
is not compatible with type "< invalidate : unit; .. >"
Self type cannot be unified with a closed object type
|}]
class closes_via_application param =
let _ = new parameter_contains_self param in
parameter_contains_self param;;
[%%expect{|
Line 3, characters 26-31:
3 | parameter_contains_self param;;
^^^^^
Error: The value "param" has type
"< redrawWidget : parameter_contains_self -> unit; .. >"
but an expression was expected of type
"< redrawWidget : < invalidate : unit; .. > -> unit; .. >"
Type "parameter_contains_self" = "< invalidate : unit >"
is not compatible with type "< invalidate : unit; .. >"
Self type cannot be unified with a closed object type
|}]
let escapes_via_inheritance param =
let module Local = struct
class c = object
inherit parameter_contains_self param
end
end in
();;
[%%expect{|
Line 4, characters 38-43:
4 | inherit parameter_contains_self param
^^^^^
Error: The value "param" has type "'a" but an expression was expected of type
"< redrawWidget : < invalidate : unit; .. > -> unit; .. >"
Self type cannot escape its class
|}]
let escapes_via_application param =
let module Local = struct
class c = parameter_contains_self param
end in
();;
[%%expect{|
Line 3, characters 38-43:
3 | class c = parameter_contains_self param
^^^^^
Error: The value "param" has type "'a" but an expression was expected of type
"< redrawWidget : < invalidate : unit; .. > -> unit; .. >"
Self type cannot escape its class
|}]
let can_close_object_via_inheritance param =
let _ = new parameter_contains_self param in object
inherit parameter_contains_self param
end;;
[%%expect{|
Line 3, characters 36-41:
3 | inherit parameter_contains_self param
^^^^^
Error: The value "param" has type
"< redrawWidget : parameter_contains_self -> unit; .. >"
but an expression was expected of type
"< redrawWidget : < invalidate : unit; .. > -> unit; .. >"
Type "parameter_contains_self" = "< invalidate : unit >"
is not compatible with type "< invalidate : unit; .. >"
Self type cannot be unified with a closed object type
|}]
let can_escape_object_via_inheritance param = object
inherit parameter_contains_self param
end;;
[%%expect{|
val can_escape_object_via_inheritance :
< redrawWidget : parameter_contains_self -> unit; .. > ->
parameter_contains_self = <fun>
|}]
let can_close_object_explicitly = object (_ : < i : int >)
method i = 5
end;;
[%%expect{|
val can_close_object_explicitly : < i : int > = <obj>
|}]
let cannot_close_object_explicitly_with_inheritance = object
inherit object (_ : < i : int >)
method i = 5
end
end;;
[%%expect{|
Line 2, characters 17-34:
2 | inherit object (_ : < i : int >)
^^^^^^^^^^^^^^^^^
Error: This pattern cannot match self: it only matches values of type
"< i : int >"
|}]
class closes_after_constraint =
((fun (x : 'a) -> object (_:'a) end) : 'a -> object('a) end) (object end);;
[%%expect{|
Line 2, characters 63-75:
2 | ((fun (x : 'a) -> object (_:'a) end) : 'a -> object('a) end) (object end);;
^^^^^^^^^^^^
Error: This expression has type "< >" but an expression was expected of type
"< .. >"
Self type cannot be unified with a closed object type
|}];;
class type ['a] ct = object ('a) end
class type closes_via_application = [ <m : int> ] ct;;
[%%expect{|
class type ['a] ct = object ('a) constraint 'a = < .. > end
Line 2, characters 38-47:
2 | class type closes_via_application = [ <m : int> ] ct;;
^^^^^^^^^
Error: The type parameter "< m : int >"
does not meet its constraint: it should be "< .. >"
Self type cannot be unified with a closed object type
|}];;
|
