Illuminate\Support\ServiceProvider::when PHP Method

    public function when()
    {
        return [];
    }

 /**
  * Register deferred service provider.
  *
  * @param  string  $provider
  * @param  \Illuminate\Support\ServiceProvider  $instance
  *
  * @return void
  */
 protected function registerDeferredServiceProvider($provider, ServiceProvider $instance)
 {
     $deferred = [];
     foreach ($instance->provides() as $provide) {
         $deferred[$provide] = $provider;
     }
     return ['instance' => $instance, 'eager' => false, 'when' => $instance->when(), 'deferred' => $deferred];
 }