Country::getAllIds

static function getAllIds(): array
{
	$reflection = new \ReflectionClass(static::class);

	$ids = [];
	foreach ($reflection->getReflectionConstants() as $const)
	{
		if (
			$const->isPublic()
			&& $const->getValue() !== static::ID_UNDEFINED
			&& (mb_strpos($const->getName(), 'ID_') !== false)
		)
		{
			$ids[] = $const->getValue();
		}
	}

	return $ids;
}