Why UFCS doesn't work with "with" statement?

[Doigt]

On Monday, 9 June 2025 at 11:39:15 UTC, Lukanian wrote:
> Why UFCS doesn't work with "with" statement?
>
> ```d
> struct MyStruct1
> {
>   int a, b;
>   int sum(){
>     return a+b;
>   }
> }
>
> int difference(ref MyStruct1 self)
> {
>   return self.a-self.b;
>
> }
>
> // in main()
>
> MyStruct1 s = { 1, 2 };
>
> s.difference().writeln; // works fine
>
> with(s){
>   sum().writeln;
>   difference().writeln; // error: too few arguments, expected 
> 1, got 0
> }
> ```

It took me a while what you were trying to do, but I think I get 
it now. I'm not an expert on D, but from what I understand, the 
reason why it doesn't work is because the difference function is 
not a method of the struct. The "with" keyword works what's a 
member of the argument. So essentially yeah, you're calling 
difference without any argument.