diff --git a/grunt/bs-raw-files-generator.js b/grunt/bs-raw-files-generator.js
index e57c2498..b7db3d58 100644
--- a/grunt/bs-raw-files-generator.js
+++ b/grunt/bs-raw-files-generator.js
@@ -11,7 +11,7 @@ var fs = require('fs');
 
 function getFiles(type, subdirs, exclude) {
   var files = {};
-  if (!exclude) exclude = [];
+  exclude = exclude || [];
   
   subdirs.forEach(function(subdir) {
     var sub = subdir ? subdir + '/' : '';