Method: (NODE-INSERT AVL-TREE-NODE T T T)

Source

(defmethod node-insert ((node avl-tree-node) k val tree)
  (with-slots (key value left right) node
    (cond ((comp-= k key) (setf value val) node)
	  ((comp-< k key)
	   (setf left (node-insert left k val tree))
	   (apply-right-rotations (adjust-height node)))
	  (t
	   (setf right (node-insert right k val tree))
	   (apply-left-rotations (adjust-height node))))))