class RedisClient

def scan_pairs(cursor_index, command)
  cursor = 0
  while cursor != "0"
    command[cursor_index] = cursor
    cursor, elements = call(*command)
    index = 0
    size = elements.size
    while index < size
      yield elements[index], elements[index + 1]
      index += 2
    end
  end
  nil
end