title: 'UIApplicationMain' attribute cannot be used in a module that contains top-level code
body: <p>All of a suden I got this error in my AppDelegate:</p>
  
  <blockquote>
    <p>'UIApplicationMain' attribute cannot be used in a module that
    contains top-level code</p>
  </blockquote>
  
  <p>in the line where it says: <code>@UIApplicationMain</code></p>
  
  <p>Now the project cannot build. I am using Swift and Xcode 6.2. I have tried deleting the derived data folder and even using the latest Xcode 6.3 beta, which was where I first created the project.</p>
  
  <p>I don't know what's going on and I have searched everywhere with no luck.
  Thank you</p>