[fpc-devel] String and UnicodeString and UTF8String

[Sven Barth]

On 13.01.2011 18:57, Hans-Peter Diettrich wrote:
>> Widestring will also grind the application to a halt due to being COM
>> based
>> on Windows.
>
> How that?
>
>

WideString on Windows has no reference counting, thus everytime a 
WideString is assigned it needs to be copied.

>>> When system encoding changes with the target platform, indexed access
>>> to such strings can lead to different results. Unless the compiler
>>> can read the coder's mind...
>>
>> You don't have to. The Delphi model provides a stringtype for the system
>> encoding, and then as such all strings from the system can be labeled.
>> With
>> other stringtypes, the necessary conversions can be edited.
>
> Indexed string access produces other results for Ansi and UTF-8 system
> encoding. Such code is not portable, and the data (ini files) are not,
> too. Allowing for UTF-8 as the system encoding will frustrate Windows
> users (dunno whether Windows allows for such a system encoding), and
> Linux users are frustrated when UTF-8 is disallowed.
>

Nearly all Windows API functions only allow single byte encodings or 
UTF-16. The only functions that I'm aware of, that can use UTF-8 
encoding is the console input/output API (if the codepage is set to 
UTF-8) [and also file I/O APIs, but they don't assume any encoding].

Regards,
Sven