public struct PersistError
{
    public PersistCode Code;
    public string Description;
    public long Bytes;

    public static implicit operator PersistCode(PersistError err)
    {
        return err.Code;
    }

    public static implicit operator int(PersistError err)
    {
        return (int) err.Code;
    }

    public bool IsOk()
    {
        return Code == 0;
    }

    public override string ToString()
    {
        return Code + (Code != PersistCode.OK ? "(" + Description + ")" : ", " + Bytes + " bytes");
    }
}