not working with codemirror.js

When I add the codemirror.js lik following , 

```
 book: {
        assets: "./book",
        js: [

            "codemirror/lib/codemirror.js"
        ],
```

I got the following error

```
Uncaught object app.js:1
makeError app.js:1
_ app.js:1
s app.js:1
requirejs app.js:1
(anonymous function)
```
