anchor.diff:                                                  | None      -> ReferenceAddress(Env(us.Path, wbname, wsname), addr) :> Reference
                                               )
                                           )
  -                                    <!> "AddressReferenceWorkbook"
  +//                                    <!> "AddressReferenceWorkbook"
       let AddressReferenceWorksheet = getUserState >>=
                                           fun us ->
                                               pipe2
                                                   (WorksheetName .>> pstring "!")
                                                   AnyAddr
                                                   (fun wsname addr -> ReferenceAddress(Env(us.Path, us.WorkbookName, wsname), addr) :> Reference)
  -                                    <!> "AddressReferenceWorksheet"
  +//                                    <!> "AddressReferenceWorksheet"
       let AddressReferenceNoWorksheet = getUserState >>=
                                           fun us ->
                                               AnyAddr
                                               |>> (fun addr -> ReferenceAddress(us, addr) :> Reference)
  -                                      <!> "AddressReferenceNOWorksheet"
  +//                                      <!> "AddressReferenceNOWorksheet"
       let AddressReference = (attempt AddressReferenceWorkbook)
                              <|> (attempt AddressReferenceWorksheet)
                              <|> AddressReferenceNoWorksheet
  
positive.code: "OFFSET"; "OR";
  "PDURATION"; "PERCENTRANK.EXC"; "PERCENTRANK.INC"; "PERCENTRANK"; "PMT"; "POISSON.DIST"; "POISSON"; "PROB"; "PRODUCT"; "PV"; 
  "RANK.AVG"; "RANK.EQ"; "RANK"; "RATE"; "REGISTER.ID"; "RRI"; "RTD"; 
  "SEARCH"; "SEARCHB"; "SKEW"; "SKEW.P"; "SLN"; "SQL.REQUEST"; "STANDARDIZE"; "STDEV"; "STDEV.P"; "STDEV.S"; "STDEVA"; "STDEVP"; "STDEVPA"; "SUBSTITUTE"; "SUBTOTAL"; "SUM"; "SUMIF"; "SUMIFS"; "SUMPRODUCT"; "SUMSQ"; "SWITCH";
  "TBILLEQ"; "TBILLPRICE"; "T.DIST"; "TDIST"; "T.DIST.2T"; "TEXTJOIN"; "TIME"; "TREND";
  "VAR"; "VAR.P"; "VAR.S"; "VARA"; "VARP"; "VARPA"; "VLOOKUP"; 
  "WORKDAY"; "WORKDAY.INTL";
  
negative.code: "ODDLPRICE"; "ODDLYIELD"; "OR";
  "PRICE"; "PRODUCT"; 
  "RTD"; 
  "STDEV"; "STDEV.P"; "STDEV.S"; "STDEVA"; "STDEVP"; "STDEVPA"; "SUBTOTAL"; "SUMIFS"; "SUMPRODUCT"; "SUMSQ"; "SWITCH";
  "TEXTJOIN"; 
  "VAR"; "VAR.P"; "VAR.S"; "VARA"; "VARP"; "VARPA"; "VDB";
  "XOR";
  