{"ast_node_type":"variable","tokens":[{"end":79,"kind":"keyword","start":0,"text":"let"}]}
        let ty = field.ty(tcx, GenericArgs::identity_for_item(tcx, field.did));
    let field_infos = adt.all_fields().map(|field| {
        let typing_env = ty::TypingEnv::non_body_analysis(tcx, field.did);