{"ast_node_type":"variable","tokens":[{"end":89,"kind":"keyword","start":0,"text":"let"}]}
            let trait_self_param = it.has_trait_self_param.then(|| toc.next()).flatten();
            let mut toc = it.params.iter_type_or_consts().map(from_toc_id(it));
            chain!(trait_self_param, it.params.iter_lt().map(from_lt_id(it)), toc)