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|
(* TEST
* expect
*)
type empty = Empty and filled = Filled
type ('a,'fout,'fin) opt =
| N : ('a, 'f, 'f) opt
| Y : 'a -> ('a, filled, empty) opt
type 'fill either =
| Either : (string, 'fill, 'f) opt * (int, 'f, empty) opt -> 'fill either;;
[%%expect{|
type empty = Empty
and filled = Filled
type ('a, 'fout, 'fin) opt =
N : ('a, 'f, 'f) opt
| Y : 'a -> ('a, filled, empty) opt
type 'fill either =
Either : (string, 'fill, 'f) opt * (int, 'f, empty) opt -> 'fill either
|}]
let f (* : filled either -> string *) =
fun (Either (Y a, N)) -> a;;
[%%expect{|
Line 2, characters 2-28:
2 | fun (Either (Y a, N)) -> a;;
^^^^^^^^^^^^^^^^^^^^^^^^^^
Warning 8 [partial-match]: this pattern-matching is not exhaustive.
Here is an example of a case that is not matched:
Either (N, Y _)
val f : filled either -> string = <fun>
|}]
|
