Major Section: PROGRAMMING
(Char-upcase x) is equal to #A when x is #a, #B when x is
#b, ..., and #Z when x is #z, and is x for any other character.
The guard for char-upcase requires its argument to be a standard
character (see standard-char-p).
Char-upcase is a Common Lisp function. See any Common Lisp
documentation for more information.