Is the flow dead?

Property definitions

nitc $ FlowContext :: is_unreachable
	# Is the flow dead?
	fun is_unreachable: Bool
	do
		# Are we explicitly marked unreachable?
		if self.is_marked_unreachable then return true

		# Are we the starting flow context?
		if is_start then return false

		# De we have a reachable previous?
		if previous.length == 0 then return true
		return false
	end
src/semantize/flow.nit:198,2--210,4