Help create process ambiguity,or bug! about ergo HOT 4 CLOSED

If I do understand you correctly... You are trying to create new gen.Server instance to start it under the Supervisor with the separated object under the hood for every single process. As you noticed, using the same object for that makes it shared between all the actors (processes spawned with this object). But... every process has a separate state which can be used within the process callbacks for your needs. Here is example

type private struct {
   i int
}

type example struct {
	gen.Server
	shared int
}

func (e *example) Init(process *gen.ServerProcess, args ...etf.Term) error {
	// State has interface{} type
	process.State = &private{i: 123} // this value is only available for this process
	e.shared = 567 // all spawned processes with the same object &example{...} have access to this value
	return nil
}
func (e *example) HandleCast(process *gen.ServerProcess, message etf.Term) gen.ServerStatus {
	state := process.State.(*private)
	fmt.Printf("[%s] HandleCast: %#v\n", process.Name(), state)

	return gen.ServerStatusOK
}

so, the answer is - this design is intentional

you may also want to see how to create a custom behavior on top of the gen.Server https://github.com/ergo-services/ergo/tree/master/examples/gendemo

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Thanks for the example! Ok, I also know that process.State can be private, but I personally prefer private objects, temporary processes that access object code is easy to write and as friendly as an Erlang Dictionary! In this example, shared sharing also needs to be lock or unlocked during operation, but I don't like unlocking because I like Mailbox

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I was thinking about your idea to create a new object for the spawned process. Pro - this object could be used as an atomic state. Cons - making a clone of provided object could be pretty hard and expensive (nested pointers, maps, slices, etc.).

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I tried to solve this problem by dynamically starting and stopping the child spec.#140

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