DIGIT-CHAR-P.html -- ACL2 Version 6.3

### DIGIT-CHAR-P

the number, if any, corresponding to a given character

    Major Section:  ACL2-BUILT-INS

`(digit-char-p ch)` is the integer corresponding to the character `ch` in base `10`. For example, `(digit-char-p #\3)` is equal to the integer `3`. More generally, an optional second argument specifies the radix (default `10`, as indicated above).

The guard for `digit-char-p` (more precisely, for the function `our-digit-char-p` that calls of this macro expand to) requires its second argument to be an integer between 2 and 36, inclusive, and its first argument to be a character.

`Digit-char-p` is a Common Lisp function, though it is implemented in the ACL2 logic as an ACL2 macro. See any Common Lisp documentation for more information.