More performant way of defining event listeners

app/server/bot/events/error.js

@@ -1,6 +1,6 @@
 module.exports = (socket) => {
 
-  socket.mcbot.on('error', (error) => {
+  function onError(error) {
 
     // this is okay because the connection was ended
     if (error.toString() === 'Error: write after end') return;
@@ -14,6 +14,8 @@ module.exports = (socket) => {
     // delete the bot
     delete socket.mcbot;
 
-  });
+  }
+
+  socket.mcbot.on('error', onError);
 
 };