gistfile1.txt

class Plane
  def initialize
    @state = "stationary"
  end
  def flying?
    @state == "flying"
  end
  def stationary?
    @state == "stationary"
  end
  def takeoff
    return false if flying
    @state == "flying"
  end
  def land
    return false if stationary?
    @state == "stationary"
  end
end