Le 27/12/2011 16:04, Andrei Alexandrescu a écrit :
On 12/27/11 5:32 AM, deadalnix wrote:
The first thing that I see looking at the source code is how many null
check you'll find in RefCounted . As the RefCounted struct is useless
without a payload, we should ensure that the payload exists, in all
cases, and not null check at every operation.
D's take on default constructor makes it impossible to initialize the
object 100% automatically. What can be done is a test inside opDispatch
followed by default construction if the object is null. That's not
terribly useful and intuitive. Consider:
That is just moving the problem around. It is even worse I think.
This is the behavior of any reference type that can be null, because
null doesn't refer to any object. IMHO this, and not null pointer
exceptions, is the largest liability of null.
Andrei
Yes, the problem is way larger. I think null is a very poor solution to
a real instanciation problem. This cause more trouble than solution. It
is error prone (forget a null check and you are doomed) and have a
runtime cost.
