A simple ping pong based actor example in Erlang

pingpong.erl

-module(pingpong).
-export([ping/0, pong/0]).

ping()->
  receive
    {Pid, ping} ->
      io:fwrite("Ping received Pong~n",[]),
      timer:sleep(3000),
      Pid ! {self(), pong},
      ping();
    stop ->
      true
    end.

pong() ->
  receive
    {Pid, pong} ->
      io:fwrite("Pong received Ping~n",[]),
      timer:sleep(3000),
      Pid ! {self(), ping},
      pong();
    stop ->
      true
    end.