char—a character.
radix—a radix.
The default is 10
.
weight—either a non-negative integer less than radix, or false.
Tests whether char is a digit in the specified radix
(i.e., with a weight less than radix).
If it is a digit in that radix,
its weight is returned as an integer;
otherwise nil
is returned.
(digit-char-p #\5) → 5 (digit-char-p #\5 2) → false (digit-char-p #\A) → false (digit-char-p #\a) → false (digit-char-p #\A 11) → 10 (digit-char-p #\a 11) → 10 (mapcar #'(lambda (radix) (map 'list #'(lambda (x) (digit-char-p x radix)) "059AaFGZ")) '(2 8 10 16 36)) → ((0 NIL NIL NIL NIL NIL NIL NIL) (0 5 NIL NIL NIL NIL NIL NIL) (0 5 9 NIL NIL NIL NIL NIL) (0 5 9 10 10 15 NIL NIL) (0 5 9 10 10 15 16 35))
None. (In particular, the results of this predicate are independent of any special syntax which might have been enabled in the current readtable.)
Digits are graphic characters.