title: Declaring empty functions in typescript
body: <p>I came over a piece of code in a custom component that I have some trouble understanding. </p>
  
  <pre class="lang-js prettyprint-override"><code>public onTouch: () =&gt; void = () =&gt; {}
  </code></pre>
  
  <p>The <code>onTouch</code> function is set by the private method </p>
  
  <pre><code>registerOnTouch(fn: any) {
    this.onTouch = fn;
  }
  </code></pre>
  
  <p>I think that the first part <code>public OnTouch: () = void</code>  declares a function without parameters that does not return a value. But I struggle to understand the last part <code>() =&gt; ()</code>.</p>
  
  <p>What does the latter part describe Could it be an overload?</p>