Gen_server respawn a new iex session in case of exception

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1

I forgot to return the expected return value in handle_call callback and when I called a function that triggered the callback, it failed with an error and gave me a completely new iex session.

Does gen_server respawn a new process if there is an exception? I thought I had to implement Supervisors to respawn a new process in case of failure.

iex:2> {:ok, cache} = Cache.start_link
{:ok, #PID<0.134.0>}
iex:3> cache
#PID<0.134.0>
iex:4> Cache.write(:stooges, [23])    

19:12:38.733 [error] GenServer CE terminating
** (stop) bad return value: %{stooges: [23]}
Last message (from #PID<0.130.0>): %{stooges: [23]}
State: %{}
Client #PID<0.130.0> is alive

    (stdlib) gen.erl:167: :gen.do_call/4
    (elixir) lib/gen_server.ex:1006: GenServer.call/3
    (stdlib) erl_eval.erl:680: :erl_eval.do_apply/6
    (elixir) src/elixir.erl:275: :elixir.eval_forms/4
    (iex) lib/iex/evaluator.ex:257: IEx.Evaluator.handle_eval/5
    (iex) lib/iex/evaluator.ex:237: IEx.Evaluator.do_eval/3
    (iex) lib/iex/evaluator.ex:215: IEx.Evaluator.eval/3
    (iex) lib/iex/evaluator.ex:103: IEx.Evaluator.loop/1
** (EXIT from #PID<0.130.0>) shell process exited with reason: bad return value: %{stooges: [23]}

After the crash

Interactive Elixir (1.9.4) - press Ctrl+C to exit (type h() ENTER for help)
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iex:1> cache
** (CompileError) iex:1: undefined function cache/0

It completely spawned a new iex session where I cant even access the cache variable

UPDATE

Ok I get it. It’s because I used start_link which linked the Cache pid into my iex session. Andthat’s the reason why my iex session was killed when there was an error in Cache

2

Yep, that links them together so one going down takes the other down too. ^.^

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