> With unions, one wants to avoid dynamic allocations. Each dynamicallocation takes several tens, sometimes, hundreds of cycles.
If pointers are used, then memory needs to be allocated for the objects they point to, whether the pointers are in a `struct' or a `union'. It needn't be allocated dynamically in either case.
I don't see any advantage to having multiple members of pointer types in a `union', e.g.,
I guess the cleanup is generally different. But use whatever you feel comfortable with.
> Unions are faster than dynamic allocations, and in the past, it wasimportant that they take little space.
I have nothing against `unions'. I think if pointers are going to be used anyway, then a single `void*' could be used for all types, in which case there would be no need for a `union'. If class types are to be allowed, the constructors of objects of these types might be performing dynamic allocation, so it might not pay to take the trouble of avoiding it for the other types. I think it's an interesting problem.
The idea with extended unions, avoiding pointers, would be to avoid having to do hand code special cleanup.
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Hans Aberg
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