Multilanguage UpCase and LowerCase

[munair]

Lazarus and Fpc use the official tables ad verbatum so that is not the case, even false information.
If it does not work it is your fault,

No.

[Thaddy]

Yes.

Examine the sources....Which you did not do.... (amateur)

If you have troubles it is your fault....

I am confining this to FPC, not Lazarus, although I expect no difference.

When you get stuck, look at the sourcecode and then you can make bold remarks:
The tables are there and - to my knowledge - correct.
Otherwise they are deferred to the OS.

The tables are machine generated from the standard of course.

There is no such thing as a FreePascal or Lazarus specific implementation.

[etrusco]

(...)
I am confining this to FPC, not Lazarus, although I expect no difference.

(...)
The tables are machine generated from the standard of course.

There is no such thing as a FreePascal or Lazarus specific implementation.

FPC's implementation indeed seems to be generated from CLDR data (in unicodedata.pas and related includes) but the version is not documented and it's not clear how it was generated (except that the author is Inoussa Ouedraogo).
I expected AnsiUpperCase() to work, but only UnicodeUpperCase(UTF8Decode()) had an effect.

Lazarus' LazUTF8 unit is an adaptation with a single case/switch (and an extra check for 'I' if you pass 'tr' in Language parameter).

[etrusco]

If I need UpCase and LowerCase for other languages than English. Then I should implement separate function for each language or is there some ready solutions for that?

UpperCase() and LowerCase() only convert chars from A to Z. This is documented in both Delphi and FPC.

[Thaddy]

Use AnsiUppercase/AnsiLowercase instead.
https://www.freepascal.org/docs-html/rtl/sysutils/ansiuppercase.html

[CM630]

.

[munair]

If you have troubles it is your fault....

I am confining this to FPC, not Lazarus, although I expect no difference.

When you get stuck, look at the sourcecode and then you can make bold remarks:

You're assuming too much. I was referring specifically to LazUTF8. I ported the entire upper- /lowercase functions and I didn't "get stuck" in doing that. They simply didn't cover every language (some only partially) and my ported functions had exactly the same functionality.

[CM630]

Well, the issue occurrs to be in the bugtracker:
https://gitlab.com/freepascal.org/lazarus/lazarus/-/issues/41444

Also:
https://forum.lazarus.freepascal.org/index.php/topic,69704.0.html