Level of the node in the tree below.
Source position: avl_tree.pp line 59
| public function TAVLTreeNode.TreeDepth: Integer; | 
The depth of the current node.
TreeDepth is the height of the node: this is the largest height of the left or right nodes, plus 1. If no nodes appear below this node (left and Right are Nil), the depth is 1.
| 
 | Balance of the current node. |