title: How to apply Composite-Iterator
body: <p>I'm trying to figure out how can i merge iterator and composite objects.
  what can be the best implementation for a struct below.</p>
  
  <pre><code>class Composite&lt;Item&gt; : Item
  {
  
  }
  
  class Iterator&lt;Item&gt;
  {
  
  }
  
  class Iterable&lt;Item&gt;
  {
  
  }
  </code></pre>