rval->ref const(T), implicit conversions

[tsbockman via Digitalmars-d]

On Monday, 18 January 2016 at 15:36:09 UTC, Manu wrote:
> One more time...
>
> Assuming:
> void func(const CustomString &s1, const CustomString &s2);
> void func(ref const(CustomString) s1, ref const(CustomString) 
> s2);
>
> C++:
>   func("hello", "world");
>
> D:
>   auto dumb_name = CustomString("hello");
>   auto another_dumb_name = CustomString("world");
>   func(dumb_name, another_dumb_name);

Actually, I was way overthinking things. Does *this* do what you 
want?

import std.stdio;

struct CustomString {
     this(string data) {
         this.data = data;
     }

     string data;
     alias data this;
}

void func(ref CustomString s1, ref CustomString s2) {
     writeln(s1);
     writeln(s2);
     s2 = "universe!";
}

pragma(inline, true)
void arFunc(T, V)(auto ref T s1, auto ref V s2) {
     func(s1, s2);
}

void main() {
     CustomString b = CustomString("world!");
     arFunc(CustomString("Hello"), b);

     writeln("Hello");
     writeln(b);
}

Again, I can probably automate generation of the wrapper easily 
enough.