# File lib/eymiha/units/units_system.rb, line 23
    def unit(attributes)
      unit = nil
      if !Units.holding_forward_reference?
        unit = UnitsUnit.new self, attributes
        self[unit.name] = unit
        Units.add_unit unit
        case unit.greek
        when :ten then greek_ten unit
        when :two then greek_two unit
        end
      else
        Units.hold_forward_reference nil
      end
      Units.continue_forward_reference_resolution
      unit
    end