Method foreach

3rdparty/libprocess/src/tests/http_tests.cpp:1947–1952

  void TearDown() override
  {
    foreach (const string& realm, realms) {
      // We need to wait in order to ensure that the operation
      // completes before we leave TearDown. Otherwise, we may
      // leak a mock object.
      AWAIT_READY(authentication::unsetAuthenticator(realm));
    }
    realms.clear();
  }