Is there an equivavlent to C# boxing in D?

[IGotD-]

On Saturday, 12 February 2022 at 00:41:22 UTC, H. S. Teoh wrote:
>
> How about this?
>
> --------
> final class Boxed(T) {
> 	T payload;
> 	alias payload this; // caveat: probably not a good idea in 
> general
> 	this(T val) { payload = val; }
> }
>
> Boxed!int i = new Boxed!int(123);
> int j = i; // hooray, implicit unboxing!
> i = 321; // even this works
> --------
>

Pretty neat solution, you need an extra type but that's not much. 
If alias this would be removed in D, would tricks like these 
suddenly become impossible?