title: 'Will never be executed'
body: <p>I don't know why this error appears in the code:</p>
  
  <pre><code>    func torpedoDidCollideWithAlien(torpedo:SKSpriteNode, alien:SKSpriteNode){
          print("HIT")
          torpedo.removeFromParent()
          alien.removeFromParent()
  
          var aliensDestroyed = 0
          aliensDestroyed += 1
  
          if (aliensDestroyed &gt; 10){ //Transition to GameOver or Success
              let transition:SKTransition = SKTransition.flipHorizontalWithDuration(0.5)
                  let gameOverScene:SKScene = GameOverScene(size: self.size, won: true)
                  self.view?.presentScene(gameOverScene, transition: transition)
              }
  </code></pre>
  
  <p>The error is at the line:</p>
  
  <pre><code>let transition:SKTransition = SKTransition.flipHorizontalWithDuration(0.5) //'Will never be executed'
  </code></pre>