init init_aissetattrexpr (
		n_kwisset: nullable TKwisset,
		n_expr: nullable AExpr,
		n_id: nullable TAttrid
	)
	do
		_n_kwisset = n_kwisset.as(not null)
		n_kwisset.parent = self
		_n_expr = n_expr.as(not null)
		n_expr.parent = self
		_n_id = n_id.as(not null)
		n_id.parent = self
	end