Can't use ES6 fat-arrow functions with arguments

see buble bug https://github.com/bublejs/buble/issues/208

modules/ui/loading.js

@@ -32,14 +32,14 @@ export function uiLoading(context) {
   };
 
 
-  loading.message = (val) => {
+  loading.message = function(val) {
     if (!arguments.length) return _message;
     _message = val;
     return loading;
   };
 
 
-  loading.blocking = (val) => {
+  loading.blocking = function(val) {
     if (!arguments.length) return _blocking;
     _blocking = val;
     return loading;

modules/ui/preset_icon.js

@@ -391,21 +391,21 @@ export function uiPresetIcon(context) {
   }
 
 
-  presetIcon.preset = (val) => {
+  presetIcon.preset = function(val) {
     if (!arguments.length) return _preset;
     _preset = utilFunctor(val);
     return presetIcon;
   };
 
 
-  presetIcon.geometry = (val) => {
+  presetIcon.geometry = function(val) {
     if (!arguments.length) return _geometry;
     _geometry = utilFunctor(val);
     return presetIcon;
   };
 
 
-  presetIcon.sizeClass = (val) => {
+  presetIcon.sizeClass = function(val) {
     if (!arguments.length) return _sizeClass;
     _sizeClass = val;
     return presetIcon;

modules/ui/success.js

@@ -359,14 +359,14 @@ export function uiSuccess(context) {
   }
 
 
-  success.changeset = (val) => {
+  success.changeset = function(val) {
     if (!arguments.length) return _changeset;
     _changeset = val;
     return success;
   };
 
 
-  success.location = (val) => {
+  success.location = function(val) {
     if (!arguments.length) return _location;
     _location = val;
     return success;