anchor.diff:      // Mutable Local Variables
       let mutable semanticHighlightingEnabled = PropertyService.Get ("EnableSemanticHighlighting", true)
       let mutable symbolsInFile: FSharpSymbolUse[] option = None
  +    let mutable colourizations = None
   
       let handlePropertyChanged =
           EventHandler<PropertyChangedEventArgs>
  
positive.code:                         |> tryCast<ParseAndCheckResults>
                          |> Option.iter (getAndProcessSymbols >> Async.Start))
  
      let makeChunk (lineNumber: int) (style: ColorScheme) (offset:int) (extraColorInfo: (Range.range * FSharpTokenColorKind)[] option) (token: FSharpTokenInfo) =
          let symbol =
              if isSimpleToken token.ColorClass then None else
              match symbolsInFile with
  
negative.code:         | Some t, s -> Some(t, s)
          | _ -> None
  
      let getLexedTokens (style, line:DocumentLine, offset, lineText) =
          let tokenizer = sourceTokenizer.CreateLineTokenizer(lineText)
          let tokens = 
              List.unfold (scanToken tokenizer) 0L
              |> List.map (makeChunk line.LineNumber style offset)
          tokens |> Seq.ofList
  
      let propertyChangedHandler = PropertyService.PropertyChanged.Subscribe handlePropertyChanged
  