		Search-engine friendly clone of the ACL2 documentation.

Representation-of-integers

Uchar-from-integer-mod

Reduce modularly ACL2 integers to values of type unsigned char.

Signature
(uchar-from-integer-mod x) → result
Arguments: x — Guard (integerp x).
Returns: result — Type (ucharp result).

Definitions and Theorems

Function: uchar-from-integer-mod

(defun uchar-from-integer-mod (x)
  (declare (xargs :guard (integerp x)))
  (let ((__function__ 'uchar-from-integer-mod))
    (declare (ignorable __function__))
    (uchar-from-integer (mod (ifix x) (1+ (uchar-max))))))

Theorem: ucharp-of-uchar-from-integer-mod

(defthm ucharp-of-uchar-from-integer-mod
  (b* ((result (uchar-from-integer-mod x)))
    (ucharp result))
  :rule-classes :rewrite)

Theorem: uchar-from-integer-mod-of-ifix-x

(defthm uchar-from-integer-mod-of-ifix-x
  (equal (uchar-from-integer-mod (ifix x))
         (uchar-from-integer-mod x)))

Theorem: uchar-from-integer-mod-int-equiv-congruence-on-x

(defthm uchar-from-integer-mod-int-equiv-congruence-on-x
  (implies (acl2::int-equiv x x-equiv)
           (equal (uchar-from-integer-mod x)
                  (uchar-from-integer-mod x-equiv)))
  :rule-classes :congruence)