Some code that compiles but shouldn't

[MoonlightSentinel]

On Monday, 30 December 2019 at 18:18:49 UTC, uranuz wrote:
> So as you see I have added a lot of enforce to test if all 
> variables are not null. But nothing was null and the reason of 
> segfault were unclear.

What about moduleName, mod and the return value of 
mod.toStdJSON()?

And whats the return type of ctx.response.write? (Returning a 
void expression is allowed and avoids some special casing in 
generic code)