Check if a value of type
Function:
(defun boolean-from-uchar (x) (declare (xargs :guard (and (ucharp x)))) (/= (integer-from-uchar x) 0))
Theorem:
(defthm booleanp-of-boolean-from-uchar (booleanp (boolean-from-uchar x)))
Theorem:
(defthm boolean-from-uchar-of-uchar-fix-x (equal (boolean-from-uchar (uchar-fix x)) (boolean-from-uchar x)))
Theorem:
(defthm boolean-from-uchar-uchar-equiv-congruence-on-x (implies (uchar-equiv x x-equiv) (equal (boolean-from-uchar x) (boolean-from-uchar x-equiv))) :rule-classes :congruence)