object TimerExample {
  /** Runs the passed in function pausing approxmimately one second in between calls.
   * as long as the function returns true. 
   */
  def oncePerSecond(callback: () => Boolean) {
    while(callback()) {
      Thread sleep 1000
    }
  }
 
  /** Counts down from 0 to 1, approxmimately once per second.
   */
  def main(args: Array[String]) {
    var count = 10
    oncePerSecond(() => {println(count); count -= 1; count > 0})
  }
}
 

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