Discussion: Rvalue refs and a Move construtor for D

[Suleyman]

On Sunday, 1 September 2019 at 08:59:08 UTC, Les De Ridder wrote:
> [...]
> Maybe a solution with a UDA is possible?

Possible.

> I'm not sure why there are three different ways to 'cast to an 
> rvalue'?
> Is there a technical reason?

I'm just demonstrating the possibilities. Likely only one of them 
will be picked.

> I also noticed you're casting lvalues to 'rvalues' and then 
> binding them a `ref` param. Is that not an rvalue reference?

Yes but I would argue this is just a perk of rvalue ref and not 
what the essence of it is.
You can do the same thing by assigning to a temporary then 
passing it by ref. This all the compiler does here.

> Why can't we have generalised rvalue references instead?

What do you need if for? Rvalue ref comes with it's own 
overloading and implicit conversion rules. Generalized rvalue ref 
is not absolutely needed for move semantics. What else comes to 
mind other than move semantics as a use case?