title: typescript multidimensional array with different types
body: <p>I have an custom object declared (ThreadObj) and I want to create a THREADLISTS, holding multiple arrays of Threadlist. So</p>
  
  <pre><code>Threadlist:ThreadObj[]=[];
  THREADLISTS:[ThreadObj[]][ThreadObj]=[][]; //how to type and init?
  </code></pre>
  
  <p>The first dim is of ThreadObj[] and the second is of ThreadObj.</p>
  
  <p>Cheers</p>