init init_alambdaexpr (
		n_kwmeth: nullable TKwmeth,
		n_signature: nullable ASignature,
		n_kwdo: nullable TKwdo,
		n_expr: nullable AExpr
	)
	do
		_n_kwmeth = n_kwmeth.as(not null)
		n_kwmeth.parent = self
		_n_signature = n_signature.as(not null)
		n_signature.parent = self
		_n_kwdo = n_kwdo.as(not null)
		n_kwdo.parent = self
		_n_expr = n_expr.as(not null)
		n_expr.parent = self
	end