🚀 go-pugleaf

wslade@atlanta.com wrote:
>I have been using enums to define error numbers within a specific class.
>I now want to derive a class from this base. I would also like to derive
>the enum from the base.
> 
>For example
>
>class A
>{
>  enum AError
>  {
>    eErrorOpen, eErrorClose
>  }
>};
> 
>class B : public A
>{
>  enum BError : AError
>  {
>    eErrorPipeOpen     // Would start at one more than AError::eErrorClose
>  }
>};
>
>Has anyone ever wanted to do this or is there another way of doing
>the same thing.

It is fairly easy to manage the enums by convention, e.g.
enum AError
{
eErrorOpen, eErrorClose, AErrorLast
}
enum BError 
{
BErrorFirst = AErrorLast, eErrorPipeOpen     // Would start at one more than
AError::eErrorClose
}

However, you cannot declare a member function that returns an AError OR a
BError (which is
probably what you are trying to do).  The closest thing I've done invloves
introducing a baseclass
and then deriving from it.  This may be quite a bit of overhead compared to
returning an int, but
it does have the advantage of a reasonably easy transition to exception
handling.
C. Sweeney


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