provider_imap/lib/Client/IdentifierMode.php

<?php

declare(strict_types=1);

namespace KTXM\ProviderImap\Client;

enum IdentifierMode
{
    case Sequence;
    case Uid;

    public function toCommand(): string
    {
        return $this === self::Uid ? 'UID FETCH' : 'FETCH';
    }
}