{"ast_node_type":"variable","tokens":[{"end":69,"kind":"keyword","start":0,"text":"let"}]}
            let base_ty = self.typeck_results.expr_ty_adjusted(base);
            // All valid indexing looks like this; might encounter non-valid indexes at this point.
            if let ty::Ref(_, base_ty_inner, _) = *base_ty.kind() {