feat: improve Js.Dict API (#974)

* feat: improve Js.Dict API

* chore: add changelog entry

Changes.md

@@ -103,6 +103,8 @@ Unreleased
   ([#972](https://github.com/melange-re/melange/pull/972))
 - BREAKING(runtime): Add labeled arguments to the callbacks in `Js.Global`
   ([#973](https://github.com/melange-re/melange/pull/973))
+- BREAKING(runtime): Add a label to `Js.Dict.map`'s function argument pipe-last
+  ([#974](https://github.com/melange-re/melange/pull/974))
 
 2.2.0 2023-12-05
 ---------------

jscomp/runtime/js_dict.ml

@@ -35,9 +35,8 @@ external unsafeGet : 'a t -> key -> 'a = ""
 [@@mel.get_index]
 (** [unsafeGet dict key] returns the value associated with [key] in [dict]
 
-This function will return an invalid value ([undefined]) if [key] does not exist in [dict]. It
-will not throw an error.
-*)
+    This function will return an invalid value ([undefined]) if [key] does not
+    exist in [dict]. It will not throw an error. *)
 
 let ( .!() ) = unsafeGet
 
@@ -53,8 +52,8 @@ external set : 'a t -> key -> 'a -> unit = ""
 [@@mel.set_index]
 (** [set dict key value] sets the value of [key] in [dict] to [value] *)
 
-external keys : 'a t -> key array = "Object.keys"
-
+external keys : 'a t -> key array = "keys"
+[@@mel.scope "Object"]
 (** [keys dict] returns an array of all the keys in [dict] *)
 
 external empty : unit -> 'a t = ""
@@ -67,24 +66,22 @@ let unsafeDeleteKey : (string t -> string -> unit[@u]) =
      }
   |}]
 
-external unsafeCreate : int -> 'a array = "Array" [@@mel.new]
+external unsafeCreateArray : int -> 'a array = "Array" [@@mel.new]
 
-(* external entries : 'a t -> (key * 'a) array = "Object.entries"  (* ES2017 *) *)
 let entries dict =
   let keys = keys dict in
   let l = Js_array.length keys in
-  let values = unsafeCreate l in
+  let values = unsafeCreateArray l in
   for i = 0 to l - 1 do
     let key = Js_array.unsafe_get keys i in
     Js_array.unsafe_set values i (key, dict.!(key))
   done;
   values
 
-(* external values : 'a t -> 'a array = "Object.values"  (* ES2017 *) *)
 let values dict =
   let keys = keys dict in
   let l = Js_array.length keys in
-  let values = unsafeCreate l in
+  let values = unsafeCreateArray l in
   for i = 0 to l - 1 do
     Js_array.unsafe_set values i dict.!(Js_array.unsafe_get keys i)
   done;
@@ -109,7 +106,7 @@ let fromArray entries =
   done;
   dict
 
-let map f source =
+let map ~f source =
   let target = empty () in
   let keys = keys source in
   let l = Js_array.length keys in

jscomp/runtime/js_dict.mli

@@ -51,8 +51,8 @@ external set : 'a t -> key -> 'a -> unit = ""
 [@@mel.set_index]
 (** [set dict key value] sets the [key]/[value] in [dict] *)
 
-external keys : 'a t -> string array = "Object.keys"
-
+external keys : 'a t -> string array = "keys"
+[@@mel.scope "Object"]
 (** [keys dict] returns all the keys in the dictionary [dict]*)
 
 external empty : unit -> 'a t = ""
@@ -64,11 +64,9 @@ module Js := Js_internal
 val unsafeDeleteKey : (string t -> string -> unit[@u])
 (** Experimental internal function *)
 
-(* external entries : 'a t -> (key * 'a) array = "Object.entries"  *)
 val entries : 'a t -> (key * 'a) array
 (** [entries dict] returns the key value pairs in [dict] (ES2017) *)
 
-(* external values : 'a t -> 'a array = "Object.values"  *)
 val values : 'a t -> 'a array
 (** [values dict] returns the values in [dict] (ES2017) *)
 
@@ -80,6 +78,6 @@ val fromArray : (key * 'a) array -> 'a t
 (** [fromArray entries] creates a new dictionary containing each
 [(key, value)] pair in [entries] *)
 
-val map : (('a -> 'b)[@u]) -> 'a t -> 'b t
+val map : f:(('a -> 'b)[@u]) -> 'a t -> 'b t
 (** [map f dict] maps [dict] to a new dictionary with the same keys,
 using [f] to map each value *)

jscomp/runtime/js_json.mli

@@ -104,7 +104,7 @@ external object_ : t Js_dict.t -> t = "%identity"
 (** [object_ dict] makes a JSON object of the [Js.Dict.t] [dict] *)
 
 external array : t array -> t = "%identity"
-(** [array_ a] makes a JSON array of the [Js.Json.t array] [a] *)
+(** [array a] makes a JSON array of the [Js.Json.t array] [a] *)
 
 (** The functions below are specialized for specific array type which
     happened to be already JSON object in the Melange runtime. Therefore

jscomp/test/js_dict_test.ml

@@ -31,6 +31,6 @@ let suites = Mt.[
     Eq([|("x", 23); ("y", 46)|], fromArray [|("x", 23); ("y", 46)|] |> entries));
   "map", (fun _ ->
     Eq( [%obj { foo = "43"; bar = "86" }] |> Obj.magic,
-        map (fun [@u] i -> string_of_int i) (obj ())))
+        map ~f:(fun [@u] i -> string_of_int i) (obj ())))
 ]
 ;; Mt.from_pair_suites __MODULE__ suites