anchor.diff:    "
   DO:      Draw the decorated TREE into the PICT.
   "
  -  (let ((box (tree-to-ascii-box      tree))
  -        (str (tree-to-ascii-formated tree))
  -        (children  (reverse (tree-to-ascii-children tree)))
  -        )
  +  (let ((box       (tree-to-ascii-box      tree))
  +        (str       (tree-to-ascii-formated tree))
  +        (children  (reverse (tree-to-ascii-children tree))))
       ;; draw the node:
       (if boxed
           (progn
  
positive.code: 
  
  (defun tree-to-ascii-compute-boxes (tree &key boxed format-fun
                                      from-length to-length)
    "
  DO:             Compute the boxes and formated strings and store them in the
                  decorated tree.
  FROM-LENGTH:    The length of the stem from the child box (default = 2).
  TO-LENGTH:      The length of the stem to the parent box (default = 2).
  RETURN:         (tree-to-ascii-box tree)
  
  
  NOTE:                     TO-LENGTH   FROM-LENGTH
                          |<--------->|<----------->|
                                                    +---------+
                                      +-------------| Child 3 |
                                      |             +---------+
                                      |
                 +--------+           |             +---------+
                 | Parent |-----------+-------------| Child 2 |
                 +--------+           |             +---------+
                                      |
  
negative.code: 
  
  (defun tree-to-ascii (tlee &key boxed format-fun background
                        to-length from-length base)
    "
  tlee:        is a list-based tree, whose car is a \"node\",
               and whose cdr is the list of children.
  