# File lib/msgpack/factory.rb, line 47
    def type_registered?(klass_or_type, selector=:both)
      case klass_or_type
      when Class
        klass = klass_or_type
        registered_types(selector).any?{|entry| klass <= entry[:class] }
      when Integer
        type = klass_or_type
        registered_types(selector).any?{|entry| type == entry[:type] }
      else
        raise ArgumentError, "class or type id"
      end
    end