Is any working sample?

Hi,
The library seems promising. So I'm doing a try.
I had installed the lib but don't know how to start to use it.
I can see some codes in the guide, for example:

``` javascript
parser.extract("length: b16, address: b32, name: b8z", function (object) {
console.log(object.length, object.address, object.name);
});
parser.parse([ 0x01, 0xFF, 0x01, 0x00, 0x00, 0x00, 0x01, 0x02, 0x00 ]);
```

However I don't know how to define the variable "parser"?

I also found the codes:

``` javascript
var parser = require('packet').createParser();
```

However, it seems **createParser()** needs **context** as argument. I don't know what the context is?

Please help.

And, yeah, a simple or relatively completed sample would be great!

Thanks.