Function foreachpair

src/master/master.cpp:1812–1817

    }
  } else if (!weights.empty()) {
    foreachpair (const string& role, double weight, weights) {
      WeightInfo weightInfo;
      weightInfo.set_role(role);
      weightInfo.set_weight(weight);
      weightInfos.push_back(weightInfo);
    }
    registrar->apply(Owned<RegistryOperation>(
        new weights::UpdateWeights(weightInfos)));
  }