代码下载到本地后，为啥执行出错？

[linlone]

我的代码结构是这样的（其中t.js是我的测试代码）

$ tree
.
├── CHANGELOG.md
├── demo
│   ├── 1409037825746-1409037838093.png
│   ├── 1409037838093-1409037882033.png
│   ├── 1409037882033-1409037916727.png
│   ├── 1409038130483-1409038137417.png
│   └── ui.png
├── index.js
├── package.json
├── phantomjs
│   ├── diff.js
│   ├── highlight.html
│   ├── highlight.js
│   ├── index.js
│   └── walk.js
├── README.md
├── t.js
└── util.js

$ cat t.js

var index = require('./index.js');

var url = 'http://www.baidu.com';
var monitor = new index.Monitor(url);
monitor.capture(function(code){
console.log(monitor.log); // from phantom
console.log('done, exit [' + code + ']');
});

为了加载phantomjs子目录下的index.js，我改成这样了：

$ head -15 index.js
。。。
var phantomjs = require('./phantomjs/index.js');
var binPath = phantomjs.path;

执行出错了，提示/phantomjs/index.js没有定义：“phantom”，这是为啥呢？？

$ node t.js

node.js:201
throw e; // process.nextTick error, or 'error' event on first tick
^
ReferenceError: phantom is not defined
at Object. (～/Desktop/Share/page-monitor-master/phantomjs/index.js:12:1)
at Module._compile (module.js:441:26)
at Object..js (module.js:459:10)
at Module.load (module.js:348:32)
at Function._load (module.js:308:12)
at Module.require (module.js:354:17)
at require (module.js:370:17)
at Object. (～/Desktop/Share/page-monitor-master/index.js:12:17)
at Module._compile (module.js:441:26)
at Object..js (module.js:459:10)