Would you please explain me that is the goal of this case?

[ashirko]

https://github.com/mrallen1/gisla/blob/4daf8e11fed6eba95a362cfccd391c8b5165866f/src/gisla.erl#L213

[jadeallenx]

It is possible that we can receive an exit message before an error message, so this just ensures that there are no other messages in our mailbox before we exit.

[ashirko]

Message 'race_conditions_are_bad_mmmkay' can be received only after receiving {complete, NewState}. Receiving {complete, NewState} means that operation_fun is completed successfuly. Moreother, demonitor(Mref, [flush]) deletes exit message if it is in a mailbox. Thus, receiving 'race_conditions_are_bad_mmmkay' is the only option after receiving {complete, NewState}.
So, maybe after receiving {complete, NewState} we should return {ok, normal, State} instead of recurcive calling 'loop', and remove 'race_conditions_are_bad_mmmkay' case?