-- main.mcl --

class c1() {
	$x = "i am x"
}

class c2() {
	include c1 as g1

	#$y = "i am y"
	$z = "i am y and " + $g1.x
}

include c2 as f1

test "${f1.z}" {}	# yep
#test "${f1.x}" {}	# no
test "${f1.g1.x}" {}	# yep

-- OUTPUT --
Vertex: test[i am y and i am x]
Vertex: test[i am x]