title: Overriding a JavaScript function while referencing the original
body: <p>I have a function, <code>a()</code>, that I want to override, but also have the original <code>a()</code> be performed in an order depending on the context. For example, sometimes when I'm generating a page I'll want to override like this:</p>
  
  <pre><code>function a() {
      new_code();
      original_a();
  }
  </code></pre>
  
  <p>and sometimes like this:</p>
  
  <pre><code>function a() {
      original_a();
      other_new_code();
  }
  </code></pre>
  
  <p>How do I get that <code>original_a()</code> from within the over-riding <code>a()</code>? Is it even possible?</p>
  
  <p>Please don't suggest alternatives to over-riding in this way, I know of many. I'm asking about this way specifically.</p>