Present -> Value, and add equivalent unboxed variant type for Null.t

Author: zth

jscomp/others/js.ml

@@ -86,7 +86,10 @@ end
 
 (**/**)
 
-type +'a null
+type +'a null =
+  | Value of 'a
+  | Null [@as null]
+[@@unboxed]
 (**
   Nullable value of this type can be either null or 'a. This type is equivalent to Js.Null.t.
 *)
@@ -97,7 +100,7 @@ type +'a undefined
 *)
 
 type +'a nullable =
-  | Present of 'a
+  | Value of 'a
   | Null [@as null]
   | Undefined [@as undefined]
 [@@unboxed]

jscomp/others/js_null.ml

@@ -25,7 +25,10 @@
 (** Provides functionality for dealing with the `'a Js.null` type *)
 
 
-type + 'a t = 'a Js.null
+type + 'a t = 'a Js.null =
+  | Value of 'a
+  | Null [@as null]
+[@@unboxed]
 
 external to_opt : 'a t -> 'a option = "#null_to_opt"
 external toOption : 'a t -> 'a option = "#null_to_opt"

jscomp/others/js_null.mli

@@ -26,7 +26,10 @@
 
 (** Provides functionality for dealing with the `Js.null('a)` type *)
 
-type +'a t = 'a Js.null
+type +'a t = 'a Js.null =
+  | Value of 'a
+  | Null [@as null]
+[@@unboxed]
 (** Local alias for `Js.null('a)` *)
 
 external return : 'a -> 'a t = "%identity"

jscomp/others/js_null_undefined.ml

@@ -25,7 +25,7 @@
 (** Contains functionality for dealing with values that can be both `null` and `undefined` *)
 
 type + 'a t = 'a Js.nullable = 
-  | Present of 'a
+  | Value of 'a
   | Null [@as null]
   | Undefined [@as undefined]
 [@@unboxed]

jscomp/others/js_null_undefined.mli

@@ -25,7 +25,7 @@
 (** Contains functionality for dealing with values that can be both `null` and `undefined` *)
 
 type +'a t = 'a Js.nullable = 
-  | Present of 'a
+  | Value of 'a
   | Null [@as null]
   | Undefined [@as undefined]
 [@@unboxed]

jscomp/runtime/js.ml

@@ -57,7 +57,10 @@ end
 (**/**)
 
 
-type + 'a null
+type + 'a null =
+  | Value of 'a
+  | Null [@as null]
+[@@unboxed]
 (** nullable, value of this type can be either [null] or ['a]
     this type is the same as type [t] in {!Null}
 *)
@@ -67,7 +70,7 @@ type + 'a undefined
     this type is the same as type [t] in {!Undefined}  *)
 
 type + 'a nullable =
-  | Present of 'a
+  | Value of 'a
   | Null [@as null]
   | Undefined [@as undefined]
 [@@unboxed]