diff --git a/lib/sig.js b/lib/sig.js
index 1eb28b45..eb7bfaa7 100644
--- a/lib/sig.js
+++ b/lib/sig.js
@@ -56,7 +56,7 @@ exports.extractFunctions = body => {
   };
   const extractNCode = () => {
     let functionName = utils.between(body, `&&(b=a.get("n"))&&(b=`, `(b)`);
-    if (functionName.includes('[')) functionName = utils.between(body, `${functionName.split('[')[0]}=[`, `]`);
+    if (functionName.includes('[')) functionName = utils.between(body, `var ${functionName.split('[')[0]}=[`, `]`);
     if (functionName && functionName.length) {
       const functionStart = `${functionName}=function(a)`;
       const ndx = body.indexOf(functionStart);