copy-ctor's

[Ola Fosheim Grøstad]

On Sunday, 26 May 2019 at 23:45:05 UTC, Ola Fosheim Grøstad wrote:
> On Sunday, 26 May 2019 at 22:33:48 UTC, Manu wrote:
>> Oh, no.. that's search results, listed recent first. I didn't 
>> realise the forum could do that.
>
> Oh yes, that can be confusing.
>
> Untagged unions doesn't really play well with destructors in 
> any language. I think C++ requires that those destructors are 
> ignored and that the union's destructor should do the cleanup. 
> Seems like a thing that is easy to forget though…

I vaguely remember Bearophile suggest that the union/struct 
should provide a means to identify which type the union was 
holding.

One usually has a union in a struct that also contains a tag of 
some sort that signifies the type of the union… but I think this 
is outside the scope of D as a language.

So perhaps one should not be allowed to have destructors in 
untagged unions and encourage the use of tagged unions…