# Generate a polymorphic attribute is_set test
	fun isset_attribute(a: MAttribute, recv: RuntimeVariable): RuntimeVariable do
		# TODO self.check_recv_notnull(recv)
		var res = new_var(compiler.mainmodule.bool_type)

		# What is the declared type of the attribute?
		var mtype = a.intro.static_mtype.as(not null)
		var intromclassdef = a.intro.mclassdef
		mtype = mtype.resolve_for(intromclassdef.bound_mtype, intromclassdef.bound_mtype, intromclassdef.mmodule, true)

		if mtype isa MNullableType then
			add("{res} = true; /* easy isset: {a} on {recv.inspect} */")
			return res
		end
		add("{res} = {recv}.attrs.get(\"{a.jname}\") != null; /* {a} on {recv.inspect} */")
		return res
	end