Thread: Enumeration of enums. Is there a way to attain something like this.

I am working on a client server based communication protocol stack.
I have a list of errors that could occur during the course of communication
Like,

Code:

Errortype        [1]
    Type1        [0]
    Type2        [1]


Type1
    Subtype1    [0]
    Subtype2    [1]


Type2
    Subtype3    [0]


Subtype1
    cause1        [0]
    cause2        [1]
    cause3        [2]


Subtype2
    cause4        [0]


Subtype3
    cause5        [0]
    cause6        [1]
    cause7        [2]
    cause8        [3]

So, if the server finds an error in connection due to cause7 of subtype3
and type2, it has to send the error report as:

Code:

errortype          : 0x01
Type       : 0x01
Subtype            : 0x00
Cause    : 0x02

So the data transferes is 01 01 00 02


I found that i can't have enum of enums in c++. And other suggestion I got
was to used a 4 byte integer for the whole error structure, so that the most significant 8 bit will show errortype, the next 8bit shows type, the next shows subtype and the least significant 8 bit shows cause. Is there any better way to do it, so that the types and subtypes and cause don't get mixed up, like type2 an't have subtype1 cause1.?