title: What does the "=> any" signify?
body: <p>In the answer to <a href="https://stackoverflow.com/questions/23021484/how-can-i-add-optional-callbacks-to-a-typescript-function">this question</a> s/he refers to:</p>
  
  <pre><code>getJSON(url: string, success?: (data: any, textStatus: string, jqXHR: JQueryXHR) =&gt; any): JQueryXHR;
  </code></pre>
  
  <p>I understand the "success?: (data: any, textStatus: string, jqXHR: JQueryXHR)" part - that's saying there is an optional function called on success that has those 3 typed parameters.</p>
  
  <p>But what does the "=> any" signify in this? Does it mean the function can return any type of object? That doesn't make sense as the success function logically is of type void.</p>
  
  <p>thanks - dave</p>