def renumber(map)
      raise "result player number #{@player} not found in renumbering hash" unless map[@player]
      self.player = map[@player]
      if @opponent
        raise "result opponent number #{@opponent} not found in renumbering hash" unless map[@opponent]
        old_rateable = @rateable
        self.opponent = map[@opponent]
        self.rateable = old_rateable  # because setting the opponent has a side-effect which is undesirable in this context
      end
      self
    end
def renumber(map)
      raise "result player number #{@player} not found in renumbering hash" unless map[@player]
      self.player = map[@player]
      if @opponent
        raise "result opponent number #{@opponent} not found in renumbering hash" unless map[@opponent]
        old_rateable = @rateable
        self.opponent = map[@opponent]
        self.rateable = old_rateable  # because setting the opponent has a side-effect which is undesirable in this context
      end
      self
    end
Renumber the player and opponent (if there is one) according to the supplied hash. Return self.