title: How to chain functions without using prototype?
body: <p>I have a bunch of useful functions that I have collected during my whole life.</p>
  
  <pre><code>function one(num){
      return num+1;
  }
  
  function two(num){
      return num+2;
  }
  </code></pre>
  
  <p>I can call them with <code>two(two(one(5)))</code></p>
  
  <p>But I would prefer to use <code>(5).one().two().two()</code></p>
  
  <p>How can I achieve this without using prototype?</p>
  
  <p>I tried to see how underscore chain works, but their code is too intense to understand it</p>