title: Class create an instance of itself
body: <p>I want an instance method of a class to create an instance of itself
  and append it to an array.</p>
  
  <p>I tried this: </p>
  
  <pre><code>var vampireArray: [Vampire] = []
  
  class Vampire {
  
    func createSelf() {  
  
        vampireArray.append(Vampire())
  
    }
  
  }
  </code></pre>
  
  <p>but I get a strange error on console like <code>(lldb)</code></p>
  
  <p>Any ideas why?</p>