First Draft: Static Single Assignment

[Tim]

On Tuesday, 18 November 2025 at 13:31:00 UTC, Quirin Schroll 
wrote:
> It were much more useful as a qualifier. If it were a 
> qualifier, it could be used in (almost?) all places it can be 
> used as a storage class, but it could *also* be used for C/C++ 
> interop, where D currently lacks the ability to represent `int* 
> const`. A `final(int*)` would be the perfect fit

For full C++ interop it would also be needed for the hidden 
`this` parameter of methods, but `final` on methods already means 
something different:
```
extern(C++) class C
{
     void f() final; // Does final mean head const here?
}
```

The syntax could distinguish between `final` before and after the 
declaration, but that could be confusing. It would be better to 
use a different keyword for head const with C++ compatibility.