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