init init_adoexpr (
		n_kwdo: nullable TKwdo,
		n_block: nullable AExpr,
		n_kwcatch: nullable TKwcatch,
		n_catch: nullable AExpr,
		n_label: nullable ALabel
	)
	do
		_n_kwdo = n_kwdo.as(not null)
		n_kwdo.parent = self
		_n_block = n_block
		if n_block != null then n_block.parent = self
		_n_kwcatch = n_kwcatch
		if n_kwcatch != null then n_kwcatch.parent = self
		_n_catch = n_catch
		if n_catch != null then n_catch.parent = self
		_n_label = n_label
		if n_label != null then n_label.parent = self
	end