{"ast_node_type":"variable","tokens":[{"end":48,"kind":"keyword","start":0,"text":"let"}]}
            let params = db.generic_params(def);
        GenericDefId::TraitId(_) | GenericDefId::TraitAliasId(_) => {
            params.trait_self_param().map(|idx| idx.into_raw().into_u32() as usize)