{"ast_node_type":"variable","tokens":[{"end":95,"kind":"keyword","start":0,"text":"let"}]}
                let num_impl_args = tcx.generics_of(impl_m.container_id(tcx)).own_params.len();
                let num_trait_args = impl_trait_ref.args.len();
                let ty = match ty.try_fold_with(&mut RemapHiddenTyRegions {