Check if the unary minus of a value of type
Function:
(defun minus-sllong-okp (x) (declare (xargs :guard (and (sllongp x)))) (sllong-integerp (- (integer-from-sllong x))))
Theorem:
(defthm booleanp-of-minus-sllong-okp (booleanp (minus-sllong-okp x)))
Theorem:
(defthm minus-sllong-okp-of-sllong-fix-x (equal (minus-sllong-okp (sllong-fix x)) (minus-sllong-okp x)))
Theorem:
(defthm minus-sllong-okp-sllong-equiv-congruence-on-x (implies (sllong-equiv x x-equiv) (equal (minus-sllong-okp x) (minus-sllong-okp x-equiv))) :rule-classes :congruence)