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