anchor.diff:          | Parser.tokenId.TOKEN_PREFIX_OP
           | Parser.tokenId.TOKEN_COLON_EQUALS
           | Parser.tokenId.TOKEN_BAR_BAR
  +        | Parser.tokenId.TOKEN_RARROW
               -> Some Punctuation
           | _ -> None
   
  
positive.code:             match tokenSymbol with
              | UnusedCode -> style.ExcludedCode
              | ComputationExpression
              | Keyword -> style.KeywordTypes
              | Comment -> style.CommentsSingleLine
              | StringLiteral -> style.String
              | NumberLiteral -> style.Number
  
negative.code:         }
  
      let (|Keyword|_|) ts =
          match ts.TokenInfo.ColorClass, ts.ExtraColorInfo with
          | FSharpTokenColorKind.Keyword, _ -> Some(Keyword)
          | _, Some (_range, extra) when extra = FSharpTokenColorKind.Keyword ->  
              Some Keyword
          | _, Some (_range, extra) ->
              None
          | _ -> None
  
      let (|Comment|_|) ts =
          if ts.TokenInfo.ColorClass = FSharpTokenColorKind.Comment then Some Comment
  