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