# File lib/html/element.rb, line 188
    def add_attribute(name, *values)
      values = values.flatten.collect { |ea| ea.to_s.strip }
      name = name.downcase
      if @_attributes.include?(name)
        @_attributes[name] = @_attributes[name].to_a + values
      else
        @_attributes[name] = values.size > 1 ? values : values[0]
      end
      @_attribute_order << name
      self
    end