src/DependencyInjection/CacheAdapterExtension.php
private function findReferences(array $options)
    {
        foreach ($options as $key => $value) {
            if (is_array($value)) {
                $options[$key] = $this->findReferences($value);
            } elseif ('_service' === substr($key, -8) || 0 === strpos($value, '@') || 'service' === $key) {
                $options[$key] = new Reference(ltrim($value, '@'));
            }
        }

        return $options;
    }
private function findReferences(array $options)
    {
        foreach ($options as $key => $value) {
            if (is_array($value)) {
                $options[$key] = $this->findReferences($value);
            } elseif ('_service' === substr($key, -8) || 0 === strpos($value, '@') || 'service' === $key) {
                $options[$key] = new Reference(ltrim($value, '@'));
            }
        }

        return $options;
    }
@param array $options

@return array