Can't "is null" an interface?!?! Incompatible types???

[Nick Sabalausky (Abscissa)]

On 03/08/2018 01:13 AM, Nicholas Wilson wrote:
> 
> That does seem odd.
> ---
> /+dub.sdl:
> dependency "vibe-d" version="~>0.8.3-alpha.1"
> +/
> import vibe.core.net;
> import std.stdio;
> TCPConnection mySocket;
> 
> void main() {
>      auto b = mySocket is null;
>      writeln(b);
> }
> ---
> works fine on run.dlang.io

Interesting. I was using vibe.d 'v0.8.3-rc.1' (which doesn't appear to 
work on run.dlang.io). But it does seem to work for me if I use 
'v0.8.3-alpha.1'.

I wonder what could have changed to result in this?