class_constant.php

<?php

namespace App\Domain;

final class Status
{
   public const DELETED = 'deleted';
   public function getDeletedStatus(): string
   {
      return self::DELETED;
    }
}

// access from FQCN
echo Status::DELETED;  // output deleted

$status = new Status;
// access from instance
echo $status::DELETED; // output deleted

// access from the class itself
echo $status->getDeletedStatus(); // output deleted