Rewrite of Data.Char library?

[Colin Paul Adams]

>>>>> "Ahn" == Ahn, Ki Yung <kyagrd at gmail.com> writes:


    Ahn> Just a follow-up to add, and my suggestions.  Lowercase and
    Ahn> Uppercase problem seems not to be solvable, since in some
    Ahn> languages like German sz doesn't have a good definition for
    Ahn> an uppercase letter.

You just follow the Unicode default foldings.

Note that these foldings are not inverses of each other - intuition is
misplaced here.
-- 
Colin Adams
Preston Lancashire