# File lib_doc/rucy/erb.rb, line 93
    def new(safe_level, pass_auth)
      case (safe_level)
      when '1', '2', '3', '4', '0'
        s = safe_level.to_i
      else
        raise "unknown safe level: #{safe_level.inspect}"
      end
      ERBFilter.new(s, pass_auth)
    end