# File lib/ferret/index.rb, line 691
691:       def ensure_writer_open()
692:         raise "tried to use a closed index" if not @open
693:         return if @writer
694:         if @reader
695:           @searcher.close if @searcher
696:           @reader.close
697:           @reader = nil
698:           @searcher = nil
699:         end
700:         @writer = IndexWriter.new(@options)
701:       end