anchor.diff:      case decode_string(Bin) of
           {error, Why} ->
               {error, Why};
  -        {Value, Rest} ->
  +        {ok, {Value, Rest}} ->
               case Mode of
                   indexing ->
                       {ok, Context2} = header:add(Name, Value, Context),
  
positive.code:     case decode_string(Bin) of
          {error, Why} ->
              {error, Why};
          {Name, Rest} ->
              decode_value(Rest, Mode, Name, Acc, Decoder)
      end.
  
  
negative.code:                                 {error, Why} ->
                                      {error, Why};
                                  Value ->
                                      {ok, {Value, Rest2}}
                              end;
                          normal ->
                              {ok, {RawValue, Rest2}}
                      end
              end
      end.
  