{"ast_node_type":"other","tokens":[{"end":77,"kind":"keyword","start":0,"text":"//"}]}
                // Curiously, we prefer object lifetime default for `+ '_`...
            self.compute_object_lifetime_bound(span, existential_predicates).unwrap_or_else(|| {
                if tcx.named_bound_var(lifetime.hir_id).is_some() {