{"ast_node_type":"variable","tokens":[{"end":46,"kind":"keyword","start":0,"text":"let"}]}
        let span = tcx.def_span(impl1_def_id);
    let Ok(impl2_args) = infcx.fully_resolve(impl2_args) else {
        let guar = tcx.dcx().emit_err(GenericArgsOnOverriddenImpl { span });