diff --git a/app/util/fast-call.js b/app/util/fast-call.js
index 3329ee5..71f4315 100644
--- a/app/util/fast-call.js
+++ b/app/util/fast-call.js
@@ -1,7 +1,7 @@
 export default function(fn, holder, args) {
   if (holder) {
     const {name} = fn;
-    if (name in holder && holder[name] === fn) {
+    if ('object' === typeof holder && name in holder && holder[name] === fn) {
       switch (args.length) {
         case 0 : return holder[name]();
         case 1 : return holder[name](args[0]);