# Collect all properties introduced in `self`
	fun collect_intro_mproperties(filter: nullable ModelFilter): Set[MProperty] do
		var set = new HashSet[MProperty]
		for mclassdef in mclassdefs do
			for mprop in mclassdef.intro_mproperties do
				if filter == null or filter.accept_mentity(mprop) then set.add(mprop)
			end
		end
		return set
	end