Check is a committee is not empty.
(committee-nonemptyp commtt) → yes/no
That is, check whether it has members.
Function:
(defun committee-nonemptyp (commtt) (declare (xargs :guard (committeep commtt))) (let ((__function__ 'committee-nonemptyp)) (declare (ignorable __function__)) (not (emptyp (committee-members commtt)))))
Theorem:
(defthm booleanp-of-committee-nonemptyp (b* ((yes/no (committee-nonemptyp commtt))) (booleanp yes/no)) :rule-classes :rewrite)
Theorem:
(defthm committee-nonemptyp-when-nonempty-subset (implies (and (subset members (committee-members commtt)) (not (emptyp members))) (committee-nonemptyp commtt)))
Theorem:
(defthm committee-nonemptyp-of-committee-fix-commtt (equal (committee-nonemptyp (committee-fix commtt)) (committee-nonemptyp commtt)))
Theorem:
(defthm committee-nonemptyp-committee-equiv-congruence-on-commtt (implies (committee-equiv commtt commtt-equiv) (equal (committee-nonemptyp commtt) (committee-nonemptyp commtt-equiv))) :rule-classes :congruence)