Am 30.11.24 um 18:16 schrieb Asmus Freytag via Unicode:
On 11/27/2024 12:15 PM, Dominikus Dittes Scherkl via Unicode wrote: However, speaking of this as a "default" is confusing to readers who think in terms of text processing or authoring environments where a different set of requirements rule. Here, the proper "default" is the best implementation of a culturally appropriate case transform.
NO. I really mean "default" in a technical sense, not something someone tailors to local needs. The ẞ was introduced to have an invertible casing, just like compatibility codepoints were assigned to make preservation of old formating information available if a translation back to some obsolete charset is necessary. _This new letter was invented to allow for 1:1 roundtrip conversion._ toUpper() shall change "ß" to "ẞ" instead of "SS", just to allow toLower() producing back "ß" instead of a wrong spelling with "ss" (which at the moment can only be avoided using a german dictionary - a really heavy constraint to a small function like toLower - and for family names simply not possible at all - the information is lost). This is a really bad situation, which should be fixed as soon as possible, not a matter of taste. And it should be fixed explicitly in automatic text processing - because this is were today errors are produced, that can now be avoided. In private letters it doesn't matter what form is used - the people write whatever they want anyway. But automatic processing shall not drop information that can not be brought back (expcept with re-introducing this knowledge back manually).
And what is "best" can change over time.
No. Fixing this round-trip bug is in the best interest of unicode and that won't change over time. Using "SS" in all uppercase text was always a bad workaround that became a source of spelling errors by automatic text processing and for which a fix was invented some ten years ago. So lets use it everywhere - at least now that it is officially allowed (since 2017) and even preferred (since this year).
