title: How to create a helper that can be access to its function name
body: <p>This my library filename: MY_is_date_helper.php</p>
  
  <pre><code>function is_date($date){
      $d = DateTime::createFromFormat('Y-m-d', $date);
      return $d &amp;&amp; $d-&gt;format('Y-m-d') == $date;
  }
  </code></pre>
  
  <p>My question is how can I call it to my MVC using just like this:</p>
  
  <pre><code>is_date('2000-01-01');
  </code></pre>
  
  <p>like what the <code>base_url()</code> did without creating any file at the system folder.</p>
  
  <p>Thanks in advance.</p>