*Org Src refile.org[ elixir ]*.ex

defmodule EventBus do
  def init do
    {:ok, _} = Registry.start_link(:duplicate, __MODULE__)
  end

  def register_handler(event_name, {m, f}, name \\ nil) do
    name = name || "#{m}##{f}"
    Registry.register(__MODULE__, event_name, {m, f, name})
  end

  def emit(event_name, args) do
    {:ok, agent} = Agent.start_link(fn -> nil end)

    Registry.dispatch __MODULE__, event_name, fn entries ->
      handler_results = for {_pid, {module, function, name}} <- entries do
          {name, apply(module, function, List.wrap(args))}
        end
      Agent.update(agent, fn _ -> handler_results end)
    end

    result = Agent.get(agent, & &1)
    Agent.stop(agent)
    result
  end
end

EventBus.init

EventBus.register_handler(:puts, {IO, :puts})
EventBus.register_handler(:puts, {IO, :inspect})

EventBus.emit(:puts, "eita")