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|
(* TEST
flags = " -w +A -strict-sequence ";
expect;
*)
(* comment 9644 of PR#6000 *)
fun b -> if b then format_of_string "x" else "y"
[%%expect {|
- : bool -> ('a, 'b, 'c, 'd, 'd, 'a) format6 = <fun>
|}, Principal{|
Line 1, characters 45-48:
1 | fun b -> if b then format_of_string "x" else "y"
^^^
Warning 18 [not-principal]: this coercion to format6 is not principal.
- : bool -> ('a, 'b, 'c, 'd, 'd, 'a) format6 = <fun>
|}]
;;
fun b -> if b then "x" else format_of_string "y"
[%%expect {|
Line 1, characters 28-48:
1 | fun b -> if b then "x" else format_of_string "y"
^^^^^^^^^^^^^^^^^^^^
Error: This expression has type
('a, 'b, 'c, 'd, 'd, 'a) format6 =
('a, 'b, 'c, 'd, 'd, 'a) CamlinternalFormatBasics.format6
but an expression was expected of type string
|}]
;;
fun b : (_,_,_) format -> if b then "x" else "y"
[%%expect {|
- : bool -> ('a, 'b, 'a) format = <fun>
|}]
;;
(* PR#7135 *)
module PR7135 = struct
module M : sig type t = private int end = struct type t = int end
include M
let lift2 (f : int -> int -> int) (x : t) (y : t) =
f (x :> int) (y :> int)
end;;
[%%expect {|
module PR7135 :
sig
module M : sig type t = private int end
type t = M.t
val lift2 : (int -> int -> int) -> t -> t -> int
end
|}]
(* example of non-ground coercion *)
module Test1 = struct
type t = private int
let f x = let y = if true then x else (x:t) in (y :> int)
end;;
[%%expect {|
module Test1 : sig type t = private int val f : t -> int end
|}, Principal{|
Line 3, characters 49-59:
3 | let f x = let y = if true then x else (x:t) in (y :> int)
^^^^^^^^^^
Warning 18 [not-principal]: this ground coercion is not principal.
module Test1 : sig type t = private int val f : t -> int end
|}]
|
