Range Redesign: Empty Ranges

[Paul Backus]

On Wednesday, 6 March 2024 at 12:20:40 UTC, Atila Neves wrote:
> I like T.init being empty. I thought I'd found a clever way to 
> make this work for classes but apparently this crashes, much to 
> my surprise:
>
> ```d
> class Class {
>     bool empty() @safe @nogc pure nothrow scope const {
>         return this is null;
>     }
> }
>
> Class c;
> assert(c.empty);
> ```

It crashes because it's attempting to access Class's vtable. If 
you make the method final, it works:

```d
class Class {
     final bool empty() {
         return this is null;
     }
}

void main()
{
     Class c;
     assert(c.empty); // ok
}
```