anchor.diff:      let result = 
           match message with
           | NestedError(position, userState, errors)          ->
  -            false, sprintf "Nested errors: %s"   <| produceErrorMessageList (indent + 1) errors
  +            false, sprintf "Nested errors: %s"   <| produceErrorMessageList errors
           | CompoundError(label, position, userState, errors) ->
  -            false, sprintf "Compound errors: %s" <| produceErrorMessageList (indent + 1) errors
  +            false, sprintf "Compound errors: %s" <| produceErrorMessageList errors
           | Expected           label -> true, expected + String.Format(CompilerMessages.LexemExpected, label)
           | ExpectedString     str
           | ExpectedStringCI   str   -> true, expected + String.Format(CompilerMessages.StringExpected, str)
  
positive.code: let private getMessage (message : string) (error : ParserError) (userState : ParserState) : string =
      if enabled then
          let position = error.Position
          sprintf "At line %d, column %d: %s" position.Line position.Column <| produceErrorMessageList 0 error.Messages
      else message
  
  let getException message (error : ParserError) userState =
  
negative.code:     | _    -> Seq.concat [Seq.singleton list.Head
                            messageSeq list.Tail]
  
  let rec private produceMessage (expectedWordWritten: bool) (message : ErrorMessage) : bool * string =
      let expected = if not expectedWordWritten
                     then "Expected "
                     else "      or "
  