title: AngularJS - How to programmatically fire validation
body: <p>I have a custom validation, for example, blacklisted. My model value and blacklisted array are the following:</p>
  
  <pre><code>model = "not_blacklisted_yet"
  blacklisted = ["foo", "bar"]
  </code></pre>
  
  <p>I want to add <code>"not_blacklisted_yet"</code> to <code>blacklisted</code>, and to fire the validation programmatically. If I just add the element, the validation is not triggered because I have not changed the models viewValue.</p>
  
  <p>How can I achieve this?</p>
  
  <p>EDIT, atach plunker: <a href="http://plnkr.co/edit/L2sJY9VOJ7s8lKCm88sM?p=preview" rel="nofollow">http://plnkr.co/edit/L2sJY9VOJ7s8lKCm88sM?p=preview</a></p>