# Collect all mproperties inehrited by 'self' with `visibility >= min_visibility`.
	fun collect_inherited_mproperties(mainmodule: MModule, filter: ModelFilter): Set[MProperty] do
		var set = new HashSet[MProperty]
		for parent in collect_parents(mainmodule, filter) do
			set.add_all(parent.collect_intro_mproperties(filter))
			set.add_all(parent.collect_inherited_mproperties(mainmodule, filter))
		end
		return set
	end