title: Use of undeclared identifier 'AppDelegate'
body: <p>Why do I get this error message with this code?
  "Use of undeclared identifier 'AppDelegate'</p>
  
  <pre><code>int main(int argc, char *argv[])
  {
      @autoreleasepool {
          return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
      }
  }
  </code></pre>