** (Advanced)
** Flags set in a [Reply Response]`OpReplyResponse` from MongoDB.
** @see ``
const class OpReplyFlags : Flag {
    ** No flags are set. Business as usual.
    static const OpReplyFlags none              := OpReplyFlags(0, "None")
    ** Set when the cursor id is not valid at the server. 
    static const OpReplyFlags cursorNotFound    := OpReplyFlags(1.shiftl(0), "CursorNotFound")
    ** Set when when query failed. Results consist of one document containing an '$err' field describing the failure.
    static const OpReplyFlags queryFailure      := OpReplyFlags(1.shiftl(1), "QueryFailure")
    ** Set when the server supports the 'AwaitData' Query option.
    static const OpReplyFlags awaitCapable      := OpReplyFlags(1.shiftl(3), "AwaitCapable")
    new make(Int flag, Str? name := null) : super(flag, name) { }