1 files changed, 30 insertions, 0 deletions
diff --git a/viz.js/dispatch.ml b/viz.js/dispatch.ml
new file mode 100755
index 0000000..42f7dc8
--- /dev/null
+++ b/viz.js/dispatch.ml
@@ -0,0 +1,30 @@
+open Js_of_ocaml
+
+type event_container =
+    E : 'a Dom.Event.typ * ('a -> unit) -> event_container
+
+type event_key = K : 'a Dom.Event.typ -> event_key
+
+type t = event_container
+
+let (catalog:event_container list ref) = ref []
+
+let register: type a. a Dom.Event.typ -> (a -> unit) -> t =
+  begin fun event callback ->
+    let handler = E (event, callback) in
+    catalog := handler::!catalog;
+    handler
+  end
+
+let remove: type a. a Dom.Event.typ -> t -> unit =
+  begin fun _event callback ->
+    catalog := List.filter (fun reg -> reg != callback)  !catalog;
+  end
+
+let call: type a. a Dom.Event.typ -> a -> unit =
+  begin fun event value ->
+    List.iter (fun (E (registered_event, callback)) ->
+        if K event = K registered_event then
+          callback (Obj.magic value)
+      ) !catalog
+  end