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