Nette\DI\Config\Helpers::takeParent PHP Method

    public static function takeParent(&$data)
    {
        if (is_array($data) && isset($data[self::EXTENDS_KEY])) {
            $parent = $data[self::EXTENDS_KEY];
            unset($data[self::EXTENDS_KEY]);
            return $parent;
        }
    }

 /**
  * @param string $name
  * @param array $config
  * @return Nette\DI\ServiceDefinition
  */
 protected function buildClient($name, $config)
 {
     $builder = $this->getContainerBuilder();
     $defaultConfig = $this->getConfig($this->clientDefaults);
     if ($parentName = Config\Helpers::takeParent($config)) {
         Nette\Utils\Validators::assertField($this->configuredClients, $parentName, 'array', "parent configuration '%', are you sure it's defined?");
         $defaultConfig = Config\Helpers::merge($this->configuredClients[$parentName], $defaultConfig);
     }
     $config = Config\Helpers::merge($config, $defaultConfig);
     $config = array_intersect_key(self::fixClientConfig($config), $this->clientDefaults);
     $client = $builder->addDefinition($clientName = $this->prefix(($name ? $name . '_' : '') . 'client'))->setClass('Kdyby\\Redis\\RedisClient', ['host' => $config['host'], 'port' => $config['port'], 'database' => $config['database'], 'timeout' => $config['timeout'], 'auth' => $config['auth'], 'persistent' => $config['persistent']]);
     if (empty($builder->parameters[$this->name]['defaultClient'])) {
         $builder->parameters[$this->name]['defaultClient'] = $clientName;
         $this->configuredClients['default'] = $config;
         $builder->addDefinition($this->prefix('default_client'))->setClass('Kdyby\\Redis\\RedisClient')->setFactory('@' . $clientName)->setAutowired(FALSE);
     } else {
         $client->setAutowired(FALSE);
     }
     $this->configuredClients[$name] = $config;
     $client->addSetup('setupLockDuration', [$config['lockDuration'], $config['lockAcquireTimeout']]);
     $client->addSetup('setConnectionAttempts', [$config['connectionAttempts']]);
     $client->addTag('redis.client');
     if (array_key_exists('debugger', $config) && $config['debugger']) {
         $builder->addDefinition($panelName = $clientName . '.panel')->setClass('Kdyby\\Redis\\Diagnostics\\Panel')->setFactory('Kdyby\\Redis\\Diagnostics\\Panel::register')->addSetup('$renderPanel', [$config['debugger'] !== self::PANEL_COUNT_MODE])->addSetup('$name', [$name ?: 'default']);
         $client->addSetup('setPanel', ['@' . $panelName]);
     }
     return $client;
 }