title: Timer.scheduledTimer Swift 3 pre-iOS 10 compatibility
body: <p>I need to schedule a Timer for firing a function every second but I see that in Xcode 8 beta 3 the scheduledTimer is only available for iOS 10.</p>
  
  <p>Is there any alternative for using the timer in iOS 9 or previous versions?</p>
  
  <pre><code>Timer.scheduledTimer(withTimeInterval: 1, repeats: true, block: { (timer) in print("Hi!")})
  </code></pre>