Basic equivalence relation for enumer structures.
Function:
(defun enumer-equiv$inline (acl2::x acl2::y) (declare (xargs :guard (and (enumerp acl2::x) (enumerp acl2::y)))) (equal (enumer-fix acl2::x) (enumer-fix acl2::y)))
Theorem:
(defthm enumer-equiv-is-an-equivalence (and (booleanp (enumer-equiv x y)) (enumer-equiv x x) (implies (enumer-equiv x y) (enumer-equiv y x)) (implies (and (enumer-equiv x y) (enumer-equiv y z)) (enumer-equiv x z))) :rule-classes (:equivalence))
Theorem:
(defthm enumer-equiv-implies-equal-enumer-fix-1 (implies (enumer-equiv acl2::x x-equiv) (equal (enumer-fix acl2::x) (enumer-fix x-equiv))) :rule-classes (:congruence))
Theorem:
(defthm enumer-fix-under-enumer-equiv (enumer-equiv (enumer-fix acl2::x) acl2::x) :rule-classes (:rewrite :rewrite-quoted-constant))
Theorem:
(defthm equal-of-enumer-fix-1-forward-to-enumer-equiv (implies (equal (enumer-fix acl2::x) acl2::y) (enumer-equiv acl2::x acl2::y)) :rule-classes :forward-chaining)
Theorem:
(defthm equal-of-enumer-fix-2-forward-to-enumer-equiv (implies (equal acl2::x (enumer-fix acl2::y)) (enumer-equiv acl2::x acl2::y)) :rule-classes :forward-chaining)
Theorem:
(defthm enumer-equiv-of-enumer-fix-1-forward (implies (enumer-equiv (enumer-fix acl2::x) acl2::y) (enumer-equiv acl2::x acl2::y)) :rule-classes :forward-chaining)
Theorem:
(defthm enumer-equiv-of-enumer-fix-2-forward (implies (enumer-equiv acl2::x (enumer-fix acl2::y)) (enumer-equiv acl2::x acl2::y)) :rule-classes :forward-chaining)