if (TRACE_actor_is_enabled()) {
s4u::Actor::on_creation_cb(on_actor_creation);
s4u::Actor::on_destruction_cb([](s4u::Actor const& actor) {
if (TRACE_actor_is_enabled()) {
s4u::Actor::on_creation_cb(on_actor_creation);
s4u::Actor::on_destruction_cb([](s4u::Actor const& actor) {