Init. Map does not function and only working on backend at the moment.

node_modules/socket.io-client/lib/on.js

@@ -0,0 +1,24 @@
+
+/**
+ * Module exports.
+ */
+
+module.exports = on;
+
+/**
+ * Helper for subscriptions.
+ *
+ * @param {Object|EventEmitter} obj with `Emitter` mixin or `EventEmitter`
+ * @param {String} event name
+ * @param {Function} callback
+ * @api public
+ */
+
+function on (obj, ev, fn) {
+  obj.on(ev, fn);
+  return {
+    destroy: function () {
+      obj.removeListener(ev, fn);
+    }
+  };
+}