I am pretty late here, but I’m afraid one can not overwrite Supervisors handle_info/2, as well as handle_call and handle_cast, because while Supervisor does not define those callbacks.
defmodule Sup do
use Supervisor
def handle_info(any, state) do
IO.inspect any
end
end
# try messaging
send(sup_pid, :hello)
Trying the above does not work, it will say something like
01:52:12.737 [error] Supervisor received unexpected message: :hello
The handle_info handle_call the Supervisor can receive seems to be defined here, and Elixir is just calling that inside def which_children, do: ....