{"ast_node_type":"other","tokens":[{"end":56,"kind":"keyword","start":0,"text":")"}]}
    ) -> Result<InferResult<'tcx, ()>, (TyVid, TyVid)> {
        predicate: ty::PolyCoercePredicate<'tcx>,
        let subtype_predicate = predicate.map_bound(|p| ty::SubtypePredicate {