How does erlang handle case statements mixed with tail recursion

Question

Let's say I have this code here:

do_recv_loop(State) ->
    receive
    {do,Stuff} ->
        case Stuff of
        one_thing -> 
            do_one_thing(),
            do_recv_loop(State);
        another_thing ->
            do_another_thing(),
            do_recv_loop(State);
        _ ->
            im_dead_now
        end
    {die} -> im_dead_now;
    _ -> do_recv_loop(State)
    end.

Now, in theory this is tail-recursive, as none of the three calls to do_recv_loop require anything to be returned. But will erlang recognize that this is tail recursive and optimize appropriately? I'm worried that the nested structure might make it not able to recognize it.

Answer 1

Yes, it will. Erlang is required to optimize tail calls, and this is clearly a tail call since nothing happens after the function is called.

I used to wish there were a tailcall keyword in Erlang so the compiler could warn me about invalid uses, but then I got used to it.