Syntax ideas for `ref` returning delegate and FP parameters

[Kagamin]

On Saturday, 10 April 2021 at 21:25:07 UTC, MoonlightSentinel 
wrote:
> Maybe allow `ref` as a postfix?
>
> ```d
> void foo(int ref delegate() dg) {}
> ```
>
> Allthough that looks kinda weird.

An obvious solution.
It's composable too:
```d
void foo(int ref delegate() ref delegate() dg) {}
```