Class 'Laravel\Nova\Nova' not found

[ahmedsaad7720]

when write command composer require tapp/select-country-code it gives me this error.

 Class 'Laravel\Nova\Nova' not found

  at C:\xampp\htdocs\niceOne\vendor\tapp\select-country-code\src\FieldServiceProvider.php:18
     14▕      * @return void
     15▕      */
     16▕     public function boot()
     17▕     {
  ➜  18▕         Nova::serving(function (ServingNova $event) {
     19▕             Nova::script('select-country-code', __DIR__.'/../dist/js/field.js');
     20▕             Nova::style('select-country-code', __DIR__.'/../dist/css/field.css');
     21▕         });
     22▕

  1   C:\xampp\htdocs\niceOne\vendor\laravel\framework\src\Illuminate\Container\BoundMethod.php:36
      Tapp\SelectCountryCode\FieldServiceProvider::boot()

  2   C:\xampp\htdocs\niceOne\vendor\laravel\framework\src\Illuminate\Container\Util.php:40
      Illuminate\Container\BoundMethod::Illuminate\Container\{closure}()
Script @php artisan package:discover --ansi handling the post-autoload-dump event returned with error code 1

Installation failed, reverting ./composer.json and ./composer.lock to their original content.

[swilla]

@amedsaad this package requires Laravel Nova, you must have that installed first. Do you have it installed?