DIP 1016--ref T accepts r-values--Final Review

[Rubn]

On Saturday, 17 November 2018 at 14:49:26 UTC, kinke wrote:
> On Saturday, 17 November 2018 at 13:01:12 UTC, Rubn wrote:
>> For this what about if there are multiple parameters? How many 
>> overloads do you have to define to get this behavior?
>
> I'd assume a single one. It should be analogous to this:
>
> ```
> void lval_only(uint x, short y) @disable;
> void lval_only(int x, int y);
>
> void main()
> {
>     byte y = 1;
>     lval_only(100_000, y);
> }
> ```
>
> The disabled function is preferred, so this doesn't compile. As 
> by-value params are to be preferred for rvalue args in overload 
> resolution, the single overload should do in your example.
>
> ---
>
> I'm a huge fan of this DIP and have been wanting this in the 
> language literally since the day I wrote my first D code, 
> immediately stumbling into this limitation (but fortunately not 
> losing much interest due to numerous advantages and syntax 
> loveliness).

If that's the case then it'll look something like this, for just 
3 parameters if you want the old behavior:

     void lval_only(int x, int y, int z) @disable;
     void lval_only(int x, int y, ref int z) @disable;
     void lval_only(int x, ref int y, ref int z) @disable;
     void lval_only(ref int x, int y, ref int z) @disable;
     void lval_only(ref int x, ref int y, int z) @disable;
     void lval_only(int x, ref int y, int z) @disable;
     void lval_only(ref int x, int y, ref int z) @disable;

     void lval_only(ref int x, ref int y, ref int z);

Not really ideal, I might be missing one, hard to tell.