anchor.diff:      return url === null ? "none" : url;
     }
   
  -  socket.on('room details', function(msg){
  -    $('#roomname h6').text(msg.room);
  +  socket.on('room details', function(change_room){
  +    $('#messages').empty();
  +    $('#roomname h6').text(change_room.room);
     });
   
     $('form').submit(function(){
  
positive.code: <script src="https://code.jquery.com/jquery-1.11.1.js"></script>
  
  <script>
  // $(function(){
    var username, change_room, user_rooms;
    if (currentUser != undefined){
  
negative.code:   <form action="">
      <input id="m" autofocus=true autocomplete="off" /><button id="send_button">Send</button>
    </form>
    <button id="random_chat">Random Chat</button>
    <div id="roomname"><h6>Lobby</h6></div>
    <ul id="messages"></ul>
  </div>
  