Bolt\Extension\Manager::register PHP Method

    public function register(Application $app)
    {
        if ($this->registered) {
            throw new \RuntimeException('Can not re-register extensions.');
        }
        foreach ($this->extensions as $extension) {
            if ($extension->isEnabled() !== true) {
                continue;
            }
            $extension->getInnerExtension()->setContainer($app);
            foreach ($extension->getInnerExtension()->getServiceProviders() as $provider) {
                $app->register($provider);
            }
        }
        $this->registered = true;
        // @deprecated Deprecated since 3.0, to be removed in 4.0.
        $this->app = $app;
    }