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