Update a stobj array
Update-nth-array is called by stobj updaters to modify stobj array fields. See stobj-example-3 for a discussion of this function and how it plays that role.
Function: update-nth-array
(defun update-nth-array (j key val l) (declare (xargs :guard (and (integerp j) (integerp key) (<= 0 j) (<= 0 key) (true-listp l) (true-listp (nth j l))))) (update-nth j (update-nth key val (nth j l)) l))
