# File lib/ferret/index.rb, line 647
647:       def ensure_writer_open()
648:         raise "tried to use a closed index" if not @open
649:         return if @writer
650:         if @reader
651:           @searcher.close if @searcher
652:           @reader.close
653:           @reader = nil
654:           @searcher = nil
655:         end
656:         @writer = IndexWriter.new(@options)
657:       end