diff --git a/port/js/src/messgen.js b/port/js/src/messgen.js
index 65afd66..36a188c 100644
--- a/port/js/src/messgen.js
+++ b/port/js/src/messgen.js
@@ -561,16 +561,17 @@ export function initializeMessages(messagesJson, headerSchema) {
         HEADER_STRUCT: headerSchema ? new Struct(headerSchema) : HEADER_STRUCT
     };
 
-    for (let m in getKeysWithSortById(messagesJson)) {
+    for (let m of getKeysWithSortById(messagesJson)) {
 
-        let name = m.trim(),
-          msg = "MSG_" + name.toUpperCase(),
-          id = messagesJson[m].id;
+      let name = m.trim(),
+        messageObj = messagesJson[m],
+        msg = "MSG_" + name.toUpperCase(),
+        id = messageObj.id;
 
-        if (!res.__id__[id]) {
-            let msg_struct = new Struct(messagesJson[m], res);
+      if (!res.__id__[id]) {
+        let msg_struct = new Struct(messageObj, res);
 
-            res.__id__[id] = msg_struct;
+        res.__id__[id] = msg_struct;
             res.__name__[id] = m.trim();
             res[msg] = msg_struct;
             res[name] = msg_struct;