# File lib/ferret/index.rb, line 851
851:       def ensure_writer_open()
852:         raise "tried to use a closed index" if not @open
853:         return if @writer
854:         if @reader
855:           @searcher.close if @searcher
856:           @reader.close
857:           @reader = nil
858:           @searcher = nil
859:         end
860:         @writer = IndexWriter.new(@options)
861:       end