```common lisp
(cl:in-package #:clump-2-3-tree)

(defgeneric delete (leaf))

(defgeneric delete-child (parent child))

(defmethod delete ((leaf leaf))
  (delete-child (parent leaf) leaf))
```

Define new generic function REPLACE-AND-SHRINK.
user
```common lisp
(cl:in-package #:clump-2-3-tree)

(defgeneric delete (leaf))

(defgeneric delete-child (parent child))

(defgeneric replace-and-shrink (parent child))

(defmethod delete ((leaf leaf))
  (delete-child (parent leaf) leaf))
```
assistant