# File lib/mongo/server_selector/selectable.rb, line 44
      def initialize(options = nil)
        options = options ? options.dup : {}
        if options[:max_staleness] == -1
          options.delete(:max_staleness)
        end
        @options = options.freeze
        @tag_sets = (options[:tag_sets] || []).freeze
        @max_staleness = options[:max_staleness]
        validate!
      end