anchor.diff:  ﻿namespace FlexSearch.Core
   
   open FlexLucene.Analysis
  -open FlexLucene.Analysis.Core
  -open FlexLucene.Analysis.Miscellaneous
   open FlexLucene.Analysis.Standard
  -open FlexLucene.Analysis.Util
  -open FlexLucene.Codecs
   open FlexLucene.Codecs.Bloom
  -open FlexLucene.Codecs.Idversion
  -open FlexLucene.Codecs.Lucene42
  -open FlexLucene.Codecs.Perfield
   open FlexLucene.Document
   open FlexLucene.Index
  -open FlexLucene.Sandbox
   open FlexLucene.Search
   open FlexLucene.Search.Similarities
  -open FlexLucene.Store
   open FlexSearch.Core
   open FlexSearch.Core.DictionaryHelpers
   open System
   open System.Collections.Concurrent
   open System.Collections.Generic
  -open System.Data
   open System.IO
   open System.Threading
  -open System.Threading.Tasks
  -open System.Threading.Tasks.Dataflow
  -open java.io
   open java.util
   open System.Diagnostics
   open System.Threading.Tasks
  
positive.code:         try 
              sw.SearcherManager.Close()
              sw.IndexWriter.Close()
          with e as AlreadyClosedException -> ()
      
      /// Adds a document to this index.
      let addDocument (document : Document) (sw : T) = sw.TrackingIndexWriter.AddDocument(document) |> ignore
  
negative.code:         /// A hook for extending classes to execute operations after pending 
          /// added and deleted documents have been flushed to the Directory but 
          /// before the change is committed (new segments_N file written).
          override __.doAfterFlush() = 
              /// State can be null when the index writer is opened for the
              /// very first time
              if not (isNull state) then state.IncrementFlushCount() |> ignore
  