{"ast_node_type":"other","tokens":[{"end":85,"kind":"keyword","start":0,"text":"arm_spans.map(|span|"}]}
            arm_spans.map(|span| (span.shrink_to_lo(), span.shrink_to_hi())).unzip();
        let (starts, ends) =
        err.subdiagnostic(SuggestBoxingForReturnImplTrait::BoxReturnExpr { starts, ends });