# replacers have less redefinitions that call super than not calling it
	private fun is_replacer(filter: ModelFilter): Bool do
		var spcs = extended_mproperties(filter).length
		var ovrs = overriden_mproperties(filter).length
		var rdfs = collect_redef_mproperties(filter).length
		if ovrs > spcs and rdfs > 0 then return true
		return false
	end