function cancelMain() {
    if (mainTask.isRunning && !mainTask.isCancelled) {
      mainTask.isCancelled = true
      next(TASK_CANCEL)
    }
  }
function cancelMain() {
    if (mainTask.isRunning && !mainTask.isCancelled) {
      mainTask.isCancelled = true
      next(TASK_CANCEL)
    }
  }
function cancelMain ( ) { if ( mainTask . isRunning && ! mainTask . isCancelled ) { mainTask . isCancelled = true next ( TASK_CANCEL ) } }
cancellation of the main task. We'll simply resume the Generator with a Cancel
cancellation of the main task . We ll simply resume the Generator with a Cancel