Function when

documentation/tutorial/tutorial.actor.cpp:67–72

	loop choose {
		when(wait(delay(0.5))) { std::cout << "Still waiting...\n"; }
		when(int r = wait(ready)) {
			std::cout << format("Ready %d\n", r);
			wait(delay(double(r)));
			std::cout << "Done\n";
			return Void();
		}
	}
}