define p_point
  set $p = ($arg0).m_i
  if ($p == 0)
    printf "null (%i)\n", $p
  else
    set $x = ($p - 1) % (Point::max_size + 2) - 1
    set $x_char = 'A' + $x
    set $y = ($p - 1) / (Point::max_size + 2) - 1
    printf "%c%i (%i)\n", $x_char, $y + 1, $p
  end
end
