diff --git a/src/scripts/01-intro.js b/src/scripts/01-intro.js
index f51e2364..6ea169cf 100644
--- a/src/scripts/01-intro.js
+++ b/src/scripts/01-intro.js
@@ -8,5 +8,5 @@
     } else {
         return factory(angular);
     }
-}(angular || null, function(angular) {
+}(typeof(angular) === 'undefined' ? null : angular, function(angular) {
     'use strict';
\ No newline at end of file