On Wed, 2023-12-13 at 16:34 +0100, Daniel Verite wrote: > In particular "el" (modern greek) has case mapping rules that > ICU seems to implement, but "el" is missing from the list > ("lt", "tr", and "az") you identified.
I compared with glibc el_GR.UTF-8 and el_CY.UTF-8 locales, and the ctype semantics match C.UTF-8 for all code points. glibc is not doing this additional tailoring for "el". Therefore I believe the builtin CTYPE would be very useful for case mapping (both "simple" and "full") even without this additional tailoring. You are correct that ICU will still have some features that won't be supported by the builtin provider. Better word boundary semantics in INITCAP() are another advantage. Regards, Jeff Davis