anchor.diff:    E last();
   
     /**
  +   * Returns a sub list copy of this list, from [start] to
  +   * [:start + length:].
  +   * Throws an [IndexOutOfRangeException] if [start] or
  +   * [:start + length:] are out of range.
  +   */
  +  List<E> getRange(int start, int length);
  +
  +  /**
      * Copies [length] elements of the [from] array, starting
      * from [startFrom], into [:this:], starting at [start].
  +   * Throws an [UnsupportedOperationException] if the list is
  +   * not extendable.
  +   * Throws an [IndexOutOfRangeException] if [start] or
  +   * [:start + length:] are out of range for [:this:], or if
  +   * [startFrom] is out of range for [from].
      */
     void setRange(int start, int length, List<E> from, [int startFrom]);
   
     /**
      * Removes the range in the list starting from [start] to
  -   * [: start + length :].
  +   * [:start + length:].
  +   * Throws an [UnsupportedOperationException] if the list is
  +   * not extendable.
  +   * Throws an [IndexOutOfRangeException] if [start] or
  +   * [:start + length:] are out of range.
      */
     void removeRange(int start, int length);
   
     /**
      * Inserts a new range in the list, starting from [start] to
  -   * [: start + length :]. The entries are filled with [initialValue].
  +   * [:start + length:]. The entries are filled with [initialValue].
  +   * Throws an [UnsupportedOperationException] if the list is
  +   * not extendable.
  +   * Throws an [IndexOutOfRangeException] if [start] or
  +   * [:start + length:] are out of range.
      */
     void insertRange(int start, int length, [E initialValue]);
  -
  -  /**
  -   * Returns a sub list of this list, starting from [start] to
  -   * [: start + length :].
  -   */
  -  List<E> getRange(int start, int length);
   }
  
positive.code:   /**
     * Appends all elements of the [collection] to the end of list.
     * Extends the length of the list by the length of [collection].
     * Throws a [UnsupportedOperationException] if the list is not
     * extendable.
     */
    void addAll(Collection<E> collection);
  
negative.code: 
    /**
     * Changes the length of the list. If [newLength] is greater than
     * the current [length], entries are initialized to [:null:]. Throws
     * an [UnsupportedOperationException] if the list is not extendable.
     */
    void set length(int newLength);
  
    /**
     * Adds [value] at the end of the list, extending the length by
     * one. Throws an [UnsupportedOperationException] if the list is not
     * extendable.
     */
    void add(E value);
  
    /**
     * Adds [value] at the end of the list, extending the length by
     * one. Throws an [UnsupportedOperationException] if the list is not
     * extendable.
     */
    void addLast(E value);
  