{"ast_node_type":"variable","tokens":[{"end":84,"kind":"keyword","start":0,"text":"let"}]}
    let hir::Node::GenericParam(param) = tcx.hir_node_by_def_id(param_def_id) else {
    debug_assert_eq!(tcx.def_kind(param_def_id), DefKind::TyParam);
        bug!("expected GenericParam for object_lifetime_default");