# File lib/ruote/dboard/mutation.rb, line 60
    def apply(dboard, option=nil)

      option ||= @type
      option = option.to_sym

      return if option != :force_update && option != @type

      type = option == :force_update ? :update : @type

      if type == :re_apply
        dboard.re_apply(@fei, :tree => @tree)
      else
        dboard.update_expression(@fei, :tree => @tree)
      end
    end