Abstract classes vs interfaces, casting from void*

[Alex]

On Sunday, 11 August 2019 at 13:09:43 UTC, John Colvin wrote:
>> Ok. What would go wrong (in D) if I just replaced every 
>> interface with an abstract class?
>
> I think there's some confusion here, because B.foo is not 
> abstract. abstract on a class is not inherited by its methods. 
> https://dlang.org/spec/attribute.html#abstract

Now, I'm confused, as you asked about abstract classes. So, yes, 
you can define the abstractness of classes differently. And what 
is your point?