Dynamic templated virtuals - I still often want them

[Steven Schveighoffer]

On 7/22/20 10:38 PM, Adam D. Ruppe wrote:

> But imagine if `serialize` actually got a virtual table entry, just like 
> if it wasn't a template at all, but each child class automatically got 
> an instance of it made for itself.

This is a great idea. Fits right in with D's philosophy of having the 
compiler write code for you so you don't have to.

I can imagine some great uses for serialization.

The syntax is probably the trickiest part of this potential feature -- 
especially since templates are automatically final, and we have no 
virtual keyword.

Potentially as well, you could specify overrides of the Base template in 
a derived type if needed.

One other tricky thing is that the override functions must not vary the 
parameter or return types (except for covariance).

-Steve