class Concurrent::Actor::Behaviour::Linking

Links the actor to other actors and sends actor’s events to them, like: ‘:terminated`, `:paused`, `:resumed`, errors, etc. Linked actor needs to handle those messages.

listener = AdHoc.spawn name: :listener do
  lambda do |message|
    case message
    when Reference
      if message.ask!(:linked?)
        message << :unlink
      else
        message << :link
      end
    else
      puts "got event #{message.inspect} from #{envelope.sender}"
    end
  end
end

an_actor = AdHoc.spawn name: :an_actor, supervise: true, behaviour_definition: Behaviour.restarting_behaviour_definition do
  lambda { |message| raise 'failed'}
end

# link the actor
listener.ask(an_actor).wait
an_actor.ask(:fail).wait
# unlink the actor
listener.ask(an_actor).wait
an_actor.ask(:fail).wait
an_actor << :terminate!

produces only two events, other events happened after unlinking

got event #<RuntimeError: failed> from #<Concurrent::Actor::Reference /an_actor (Concurrent::Actor::Utils::AdHoc)>
got event :reset from #<Concurrent::Actor::Reference /an_actor (Concurrent::Actor::Utils::AdHoc)>