[fpc-devel] new string - question on usage

[Paul Ishenin]

13.10.2011 9:13, Hans-Peter Diettrich wrote:
> Sven Barth schrieb:
>
>> http://svn.freepascal.org/cgi-bin/viewvc.cgi/trunk/rtl/inc/astrings.inc?revision=19444&view=markup
>>
>
> I don't understand the use of encoding 0 and CP_NONE in FPC. Can
> somebody explain?

DefaultSystemCodepage is used When the paticular encoding must be known 
both for 0 and CP_NONE codepages.

> Furthermore I suspect that the implementation of
>
> Function Pos(Const Substr : RawByteString; Const Source : RawByteString)
> : SizeInt;
>
> is wrong. The comparison must take into account the encodings of both
> strings.
>
>
> Function Pos(c : AnsiChar; Const s : RawByteString) : SizeInt;
> is questionable at all, when the encoding of the arguments is unknown or
> ignored (as is).

Did you run some tests in delphi for these functions?

Please run the next program to be sure:

{$apptype console}

type
   T866Sting = type AnsiString(866);
   T1251String = type AnsiString(1251);
var
   s866: T866Sting;
   s1251: T1251String;
begin
   s866 := 'привет';
   writeln(s866);
   s1251 := 'рив';
   writeln(s1251);
   writeln(pos(s1251, s866));
end.

> I have the bad impression that the implementors didn't understand the
> purpose and correct use of RawByteString, or try to implement something
> incompatible with Delphi :-(

Do you base your impression on paticular knowlege of how delphi RTL 
works or only on your ideas of how it should work?

Best regards,
Paul Ishenin.