protected function ensureInterfacesExist($interfaces, $stmt)
    {
        foreach ($interfaces as $interface) {
            /** @var string $name */
            $name = $this->getFullyQualifiedName($interface);
            if (!$this->interfaceExists($name)) {
                throw $this->createError(\sprintf('Interface \'%s\' not found', $name), $stmt);
            }
        }
    }