{"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":"vec![None;"}]}
            vec![None; self.subtree.len()];
        let mut res: Vec<Option<(tt::Delimiter<S>, Vec<tt::TokenTree<S>>)>> =
        let read_span = |id| S::span_for_token_id(self.span_data_table, id);