The function unicode-both-case-p
returns flag as true if char has case according to the Unicode rules specified by style.
The name of unicode-both-case-p
is slightly confusing, because it matches the ANSI Common Lisp definition "a character with case" whereas there is no guarantee that both cases actually exist. Note also that there are some "alpha" chars which are not lower or upper case.
LispWorks User Guide and Reference Manual - 20 Sep 2017