title: Class extension inside a playground
body: <p>I have a UIVIew subclass in my playground sources folder (its a Public class) and I'm trying to only put a portion of this class into my main playground file as an extension. </p>
  
  <p>When I declare the following in my playground </p>
  
  <pre><code>public extension SortingAlgorithmView {
  
      public func typeTest() {
          print("dfasfndjasfasfdasfdasf test ")
      }
  }
  </code></pre>
  
  <p>and then inside my subclass I call typeTest() it tells me there is no function with the name typeTest.</p>