first shot at onresize

js/lib.js

@@ -46,6 +46,12 @@ Haskell.on = function (el, eventType, fun) {
       fun(e.keyCode);
       return true;
     });
+  } else if(eventType === 'resize') {
+    window.onresize = function(e) {
+      var t = e.target;
+      fun([t.innerWidth, t.innerHeight]);
+      return true;
+    };
   } else {
     $(el).on(eventType, function(e) {
       fun(e.which ? [e.which.toString()] : e.detail || []);

src/Graphics/UI/Threepenny/Events.hs

@@ -8,7 +8,7 @@ module Graphics.UI.Threepenny.Events (
     -- * Standard DOM events
     click, contextmenu, mousemove, mousedown, mouseup,
     hover, leave,
-    focus, blur,
+    focus, blur, resize,
     KeyCode, keyup, keydown,
     ) where
 
@@ -87,6 +87,11 @@ focus = silence . domEvent "focus"
 blur :: Element -> Event ()
 blur = silence . domEvent "blur"
 
+-- | Element reports its window's resize.
+--   Note that there should only be at most one
+--   'resize' event registered.
+resize :: Element -> Event (Int,Int)
+resize = fmap readCoordinates . domEvent "resize"
 
 type KeyCode = Int