Get the digit1 field from a oct-escape-two.
(oct-escape-two->digit1 x) → digit1
This is an ordinary field accessor created by fty::defprod.
Function:
(defun oct-escape-two->digit1$inline (x) (declare (xargs :guard (oct-escapep x))) (declare (xargs :guard (equal (oct-escape-kind x) :two))) (let ((__function__ 'oct-escape-two->digit1)) (declare (ignorable __function__)) (mbe :logic (b* ((x (and (equal (oct-escape-kind x) :two) x))) (str::oct-digit-char-fix (std::da-nth 0 (cdr x)))) :exec (std::da-nth 0 (cdr x)))))
Theorem:
(defthm oct-digit-char-p-of-oct-escape-two->digit1 (b* ((digit1 (oct-escape-two->digit1$inline x))) (oct-digit-char-p digit1)) :rule-classes :rewrite)
Theorem:
(defthm oct-escape-two->digit1$inline-of-oct-escape-fix-x (equal (oct-escape-two->digit1$inline (oct-escape-fix x)) (oct-escape-two->digit1$inline x)))
Theorem:
(defthm oct-escape-two->digit1$inline-oct-escape-equiv-congruence-on-x (implies (oct-escape-equiv x x-equiv) (equal (oct-escape-two->digit1$inline x) (oct-escape-two->digit1$inline x-equiv))) :rule-classes :congruence)
Theorem:
(defthm oct-escape-two->digit1-when-wrong-kind (implies (not (equal (oct-escape-kind x) :two)) (equal (oct-escape-two->digit1 x) (str::oct-digit-char-fix nil))))