[:] as empty associative array literal, plus warning for null

[TommiT]

On Thursday, 4 July 2013 at 13:32:25 UTC, Steven Schveighoffer 
wrote:
> On Thu, 04 Jul 2013 08:52:12 -0400, Regan Heath wrote:
>> Indeed.  IMO if(arr) should mean if(arr.ptr) .. and I thought 
>> it did.. or did this change at some point?
>
> No, it should mean if(arr.length).  It means if(arr.ptr) now, 
> and this is incorrect.  [..]

The meaning of if(x) for all x of nullable types has always been 
if(x != null) probably in all languages.