# File log4r/yamlconfigurator.rb, line 29
    def self.custom_levels( levels)
      return Logger.root if levels.size == 0
      for i in 0...levels.size
        name = levels[i].to_s
        if name =~ /\s/ or name !~ /^[A-Z]/
          raise TypeError, "#{name} is not a valid Ruby Constant name", caller
        end
      end
      Log4r.define_levels *levels
    end