Get the arg field from a jexpr-postinc.
This is an ordinary field accessor created by fty::defprod.
Function:
(defun jexpr-postinc->arg$inline (x) (declare (xargs :guard (jexprp x))) (declare (xargs :guard (equal (jexpr-kind x) :postinc))) (let ((__function__ 'jexpr-postinc->arg)) (declare (ignorable __function__)) (mbe :logic (b* ((x (and (equal (jexpr-kind x) :postinc) x))) (jexpr-fix (std::da-nth 0 (cdr x)))) :exec (std::da-nth 0 (cdr x)))))
Theorem:
(defthm jexprp-of-jexpr-postinc->arg (b* ((arg (jexpr-postinc->arg$inline x))) (jexprp arg)) :rule-classes :rewrite)
Theorem:
(defthm jexpr-postinc->arg$inline-of-jexpr-fix-x (equal (jexpr-postinc->arg$inline (jexpr-fix x)) (jexpr-postinc->arg$inline x)))
Theorem:
(defthm jexpr-postinc->arg$inline-jexpr-equiv-congruence-on-x (implies (jexpr-equiv x x-equiv) (equal (jexpr-postinc->arg$inline x) (jexpr-postinc->arg$inline x-equiv))) :rule-classes :congruence)
Theorem:
(defthm jexpr-postinc->arg-when-wrong-kind (implies (not (equal (jexpr-kind x) :postinc)) (equal (jexpr-postinc->arg x) (jexpr-fix nil))))