在Zork之类的游戏中遇到JS麻烦-保持未定义状态，而不是预期的文本

Question

我正在观看有关如何使用JavaScript和jQuery制作类似于Zork的游戏的教程。到目前为止，它一直在工作，但是当我尝试使用方向命令更改运行游戏的位置时，我得到的是不确定的，而不是新的房间。

var currentRoom = "start" ;

function changeRoom(dir) {
  if(rooms[currentRoom].directions[dir] !== undefined) {
    currentRoom = rooms[currentRoom].directions[dir];
    $('#game-text').append("<p>" + rooms[currentRoom].description + "</p>");
  } else {
      $('#game-text').append("<p> You cannot go that way </p>");
  }
}

编辑：此代码位于上面的代码之后

$(document).ready(function(){
    $('#game-text').append("<p>" + rooms.start.description + "</p>");

    $(document).keypress(function(key){
      if(key.which === 13 && $('#user-input').is(':focus')){
          var value = $('#user-input').val().toLowerCase();
          switch(value) {
            case "north":
              changeRoom("north");
              break;
            case "south":
              changeRoom("south");
              break;
              case "east":
              changeRoom("east");
              break;
              case "west":
              changeRoom("west");
              break;
            default:
              alert("Invalid move!")
          }
      }
    })

})

我认为这与这段代码有关。出现“您不能那样走”消息时，应该出现；但是我没有得到我进入的房间的描述，只有一条未定义的消息。抱歉，如果我不清楚，这是我的拳头尝试，我对JavaScript知之甚少。

编辑：这是两个“房间”。

var rooms = {
  "start": {
    "description": "It is a sunny day, perfect for a walk!\
    While walking, you come across an intersection;\
    you can go <b>North</b>, <b>South</b>, <b>East</b> or\
    <b>West</b>, which way do you choose?",
  "directions": {
    "north": "deadend",
    "west": "shortcut",
    "east": "garden",
    "south": "home"
    }
  "garden": { 
    "discription": "Ahh the right path, I see you choose the long\
  way around which leads through a lovley garden",
    "directions": {
      "west": "start",
      "east": "deadend"
    }
  },