Get the kind (tag) of a nat/natlist structure.
(nat/natlist-kind x) → kind
Function:
(defun nat/natlist-kind$inline (x) (declare (xargs :guard (nat/natlist-p x))) (let ((__function__ 'nat/natlist-kind)) (declare (ignorable __function__)) (mbe :logic (cond ((or (atom x) (eq (car x) :one)) :one) (t :list)) :exec (car x))))
Theorem:
(defthm nat/natlist-kind-possibilities (or (equal (nat/natlist-kind x) :one) (equal (nat/natlist-kind x) :list)) :rule-classes ((:forward-chaining :trigger-terms ((nat/natlist-kind x)))))