Range golf challenge: apply predicate to a subrange, returning the original range modified.

[Andrey Zherikov]

On Friday, 7 October 2022 at 16:32:07 UTC, Andrey Zherikov wrote:
> ```d
> 10.iota.map!(_ => _.isEven ? _*2 : _); // => [0, 1, 4, 3, 8, 5, 
> 12, 7, 16, 9]
> ```

You can even generalize this:
```d
alias mapSubrange(alias filter, alias transform) = map!(_ => 
filter(_) ? transform(_) : _);
10.iota.mapSubrange!(isEven, _ => _*2);
```