You need more tables for case folding. Also, case-folding doesn't round-trip in Unicode. In particular, only to-lower-case conversions work well enough. Case

You need more tables for case folding. Also, case-folding doesn't round-trip in Unicode. In particular, only to-lower-case conversions work well enough. Case is a mistake. Case-insensitivity is another mistake though. Don't do it. It's a pain for users (me, for example).