Brainstorming: Explicit instantiation of function template with `auto ref` parameters

[Dukc]

On Thursday, 20 February 2025 at 23:24:10 UTC, Quirin Schroll 
wrote:
> Function templates with `auto ref` parameters can’t be 
> explicitly instantiated, but must be IFTI’d to infer `ref`-ness 
> of `auto ref` parameters.

I thought you could at least do it if I was willing to jump 
through the hoops to completely specify the function type I was 
trying to instantiate:

```D
void example(Ts...)(auto ref int arg, auto ref Ts args)
{	import std.stdio;
	writeln(is(typeof(&arg))? "lvalue " : "rvalue ", arg);
}

void main()
{	void function(int) fPtr1 = &example!();
	void function(ref int) fPtr2 = &example!();
	
	fPtr1(10);
	fPtr2(*new int(20));
}
```

. But the compiler plain out stated
```
app.d(1): Error: cannot explicitly instantiate template function 
with `auto ref` parameter
```
, so this problem is even worse than I thought. I agree some sort 
of solution is needed, though I don't have a good idea what it 
should be like.