Hack-like attributes

attributes.php

<?php declare(strict_types=1);

/**
 * Builtin interfaces for attributes :
 * - ClassAttribute
 * - FunctionAttribute
 * - TypeParameterAttribute
 * - MethodAttribute
 * - StaticPropertyAttribute
 * - EnumAttribute
 * - InstancePropertyAttribute
 * - TypeAliasAttribute
 * - PropertyAttribute
 * - ClassLikeAttribute 
 * - FileAttribute
 *
 * see : https://docs.hhvm.com/hack/attributes/introduction
 * see : https://docs.hhvm.com/hack/reference/interface
 */

namespace Doctrine\Orm {
  use ClassAttribute;
  use PropertyAttribute;
  
  final class Entity implements ClassAttribute {
    public string $table;
    
    public function __construct(string $table) {
      $this->table = $table;
    }
  }
  
  final class Column implements PropertyAttribute {}
  final class Id implements PropertyAttribute {}
}

namespace App\Entity {
  use Doctrine\Orm;
  
  <<Orm\Entity('users')>>
  final class User {
    <<Orm\Id(), Orm\Column()>>
    public int $id;
    
    <<Orm\Column()>>
    public string $name;
    
    public function __construct(int $id, string $name) {
      $this->id = $id;
      $this->name = $name;
    }
  }
}

namespace {
  $rc = ReflectionClass(App\Entity\User::class);
  /**
   * @var null|Doctrine\Orm\Entity $entity
   */
  $entity = $rc->getAttributeClass(Doctrine\Orm\Entity::class);
  if (null === $entity) {
    echo 'class doesn\'t have the entity attribute';
  } else {
    echo $entity->table;
  }
}