gistfile1.txt

notification default {
	print = true
}

notification nc1 {
	print = true
}

notification nc2 {
	print = true
}

notification nc3 {
	print = true
}

notification nc4 {
	print = true
}

lookup nc {
	entry host=ny-* {
		v = nc1
	}
	entry host=nyhq-* {
		v = nc2
	}
	entry host=* {
		v = nc1,nc3
	}
}

alert nc {
	crit = 1
	critNotification = default,nc4
	critNotification = lookup("nc", "v")
	# not allowed:
	# critNotification = default,lookup("nc", "v")
}

critNotification can now be specified multiple times, with the values merging with each other. The lookup function can return something already in the list and it will be triggered only once.