delete

func delete(ls : List+String, i : Integer) -> List+String
  return slice(ls, [1..i-1]) + slice(ls, [i+1..#ls])

Returns a copy of the given list or string, but without the i-th element. Returns Undefined if the given index is less than one or greater than the length of the list or string. For example:

  delete(`abc', 2) = `ac'
  delete([1 2 3], 1) = [2 3]
  delete([1 2 3], 4) = Undefined