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|
type foo = ..
;;
(* Check that abbreviations work *)
type bar = foo = ..
;;
type baz = foo = ..
;;
type bar += Bar1 of int
;;
type baz += Bar2 of int
;;
module M = struct type bar += Foo of float end
;;
module type S = sig type baz += Foo of float end
;;
module M_S = (M : S)
;;
(* Abbreviations need to be made open *)
type foo = ..
;;
type bar = foo
;;
type bar += Bar of int (* Error: type is not open *)
;;
type baz = bar = .. (* Error: type kinds don't match *)
;;
(* Abbreviations need to match parameters *)
type 'a foo = ..
;;
type ('a, 'b) bar = 'a foo = .. (* Error: arrities do not match *)
;;
type ('a, 'b) foo = ..
;;
type ('a, 'b) bar = ('a, 'a) foo = .. (* Error: constraints do not match *)
;;
(* Private abstract types cannot be open *)
type foo = ..
;;
type bar = private foo = .. (* ERROR: Private abstract types cannot be open *)
;;
(* Check that signatures can hide open-ness *)
module M = struct type foo = .. end
;;
module type S = sig type foo end
;;
module M_S = (M : S)
;;
type M_S.foo += Foo (* ERROR: Cannot extend a type that isn't "open" *)
;;
(* Check that signatures cannot add open-ness *)
module M = struct type foo end
;;
module type S = sig type foo = .. end
;;
module M_S = (M : S) (* ERROR: Signatures are not compatible *)
;;
(* Check that signatures maintain variances *)
module M = struct type +'a foo = .. type 'a bar = 'a foo = .. end
;;
module type S = sig type 'a foo = .. type 'a bar = 'a foo = .. end
;;
module M_S = (M : S) (* ERROR: Signatures are not compatible *)
;;
(* Exn is an open type *)
type exn2 = exn = ..
;;
(* Exhaustiveness *)
type foo = ..
type foo += Foo
let f = function Foo -> ()
;; (* warn *)
|
