# equals contain as redifinition than introduction
	private fun is_equal(filter: ModelFilter): Bool do
		var spcs = extended_mproperties(filter).length
		var ovrs = overriden_mproperties(filter).length
		var rdfs = collect_redef_mproperties(filter).length
		if spcs == ovrs and rdfs > 0 then return true
		return false
	end