anchor.diff:                drop' (n - 1) ++ [ (elemAt list n) ];
           in drop' (len - 1);
   
  -
  -  # Return a list consisting of at most ‘count’ elements of ‘list’,
  -  # starting at index ‘start’.
  +  /* Return a list consisting of at most ‘count’ elements of ‘list’,
  +     starting at index ‘start’.
  +
  +     Example:
  +       sublist 1 3 [ "a" "b" "c" "d" "e" ]
  +       => [ "b" "c" "d" ]
  +       sublist 1 3 [ ]
  +       => [ ]
  +  */
     sublist = start: count: list:
       let len = length list; in
       genList
  
positive.code:       if len < 2 then list
        else (sort strictLess pivot.left) ++  [ first ] ++  (sort strictLess pivot.right));
  
  
    # Return the first (at most) N elements of a list.
    take =
      if builtins ? genList then
        count: sublist 0 count
  
negative.code:         xs = unique (drop 1 list);
        in [x] ++ remove x xs;
  
    /* Intersects list 'e' and another list. O(nm) complexity.
  
       Example:
         intersectLists [ 1 2 3 ] [ 6 3 2 ]
         => [ 3 2 ]
    */
    intersectLists = e: filter (x: elem x e);
  
    /* Subtracts list 'e' from another list. O(nm) complexity.
  
       Example:
         subtractLists [ 3 2 ] [ 1 2 3 4 5 3 ]
         => [ 1 4 5 ]
    */
    subtractLists = e: filter (x: !(elem x e));
  
    /*** deprecated stuff ***/
  
    deepSeqList = throw "removed 2016-02-29 because unused and broken";
  
  }
  