According to the docs here: <https://facebook.github.io/immutable-js/docs/#/Map/getIn>

I should be able to get the deeply nested value by providing an array for the `keyPath` argument. This is what I've done, however I'm getting `undefined` as the return value.

<http://jsfiddle.net/srxv4mwu/>

```
var obj = Immutable.Map({categories: {1: 'a', 2: 'b'}});
var output = obj.getIn(['categories', 1]);
alert(output);

```

What am I doing wrong?