'Microsoft\PhpParser\Node\Statement\ReturnStatement' => static function (PhpParser\Node\Statement\ReturnStatement $n, int $start_line): ast\Node {
                $e = $n->expression;
                $expr_node = $e !== null ? static::phpParserNodeToAstNode($e) : null;
                return new ast\Node(ast\AST_RETURN, 0, ['expr' => $expr_node], $start_line);
            },