A weird example of .toUTF16z concatination side-effects in wcsncat

[Tejas]

On Thursday, 7 April 2022 at 10:50:35 UTC, BoQsc wrote:
> Here I try to concatenate three character strings using 
> `wcsncat()`.
>
> [...]

Maybe try using `wstring` instead of string? Also use the `w` 
postfix

```d
wstring dlang_string = "BBBBBBBBBBB"w;

I can't test because I'm not on my PC and I don't use Windows