text: function Timer() {}
  
  // Returns the amount of time (in milliseconds) left for the player.
  Timer.prototype.timeLeftForPlayer = function(player) {
    throw new Error("This method needs to be implemented by the subclass.");
  };
  
  // Attempt to tap the clock as the specified player at the specified time.
  // Tapping the clock when it is not your turn is a NO-OP that returns true.
  // Returns false if the player is out of time.
  // Returns true otherwise.
  Timer.prototype.tapClock = function(player, timestamp) {
    throw new Error("This method needs to be implemented by the subclass.");
  };
  
  module.exports = Timer;
  