just an idea (!! operator)

[Christophe Travert]

"David Piepgrass" , dans le message (digitalmars.D:172164), a écrit :
>>> Yeah, I've been planning to try and get this into D one day.  
>>> Probably
>>> something like:
>>> (a ?: b) ->  (auto __tmp = a, __tmp ? __tmp : b)
>>
>> gcc used to have that extension and they dropped it...
> 
> But GCC can't control the C++ language spec. Naturally there is a 
> reluctance to add nonstandard features. It's a successful feature 
> in C#, however, and a lot of people (including me) have also been 
> pestering the C# crew for "null dot" (for safely calling methods 
> on object references that might be null.)
> 
> I don't see why you would use ?: instead of ??, though.

Because ?: is the ternary conditionnal operator with missing 
second operand.

a ?: b // or maybe a ? : b
is just a short hand for
a ? a : b
(except a is evaluated only once).