def add_filters( *args )
    args.flatten.each do |filter|
      next if filter.nil?
      unless filter.kind_of?(::Logging::Filter)
        raise TypeError, "#{filter.inspect} is not a kind of 'Logging::Filter'"
      end
      @filters << filter
    end
    self
  end
def add_filters( *args )
    args.flatten.each do |filter|
      next if filter.nil?
      unless filter.kind_of?(::Logging::Filter)
        raise TypeError, "#{filter.inspect} is not a kind of 'Logging::Filter'"
      end
      @filters << filter
    end
    self
  end
Sets the filter(s) to be used by this appender. The filters will be
 applied in the order that they are added to the appender.

 Examples
    add_filters(Logging::Filters::Level.new(:warn, :error))

 Returns this appender instance.