Is there a way in typescript define fixed size array. say, for example, in a function definition, I need to able to say

```
coord: (c:any) => number[]; //how to say it is an array of size 4

```

can I define an interface like we define a hash map

```
//this doesn't work
interface IArray{
  [number]
}

```

and also restrict max length to be 4.