title: NodeJS watcher printing undefined after logging function to console
body: <p>I am playing around with NodeJS watchers and have written something like this in <code>debugger.js</code>:</p>
  
  <pre><code>setTimeout(() =&gt; {
    debugger;
    var z = () =&gt; {console.log('today');}
    console.log(z());
  }, 1000);
  console.log('hello');
  </code></pre>
  
  <p>I then run <code>node debug debugger.js</code> in Git Bash which returns:</p>
  
  <pre><code>break in C:\Users\Eigenaar\OneDrive\dev\NodeJS\debugger.js:1
  &gt; 1 x = 5;
    2 setTimeout(() =&gt; {
    3   debugger;
  </code></pre>
  
  <p>I hit <code>c</code> couple of times to run through the debugging process. In the end I get:</p>
  
  <pre><code>&lt; today
  &lt; undefined
  </code></pre>
  
  <p>Why is undefined being returned? What is undefined?</p>