References in D

[bearophile]

Timon Gehr:

>> To quote (loosely) Mr. Walter Bright from another discussion: 
>> how many
>> current bugs in dmd are related to default null references?
>
> More than zero.

A >0 frequency of bugs caused by something can't be enough to 
justify a language feature. You need a "high enough" frequency :-)

--------------------------

Alex Burton:

>> Doing null references in C++ is simple:
>>
>> int *p = NULL;
>> int& r = *p;
>>
>> r = 3; // crash
>
>
> IMHO int * p = NULL is a violation of the type system and 
> should not compile.
> NULL can in no way be considered a pointer to an int.

I don't agree. int* is a raw pointer, and a raw pointer is 
allowed to contain a null, so the first line is OK.

The problem is in the second line: in a better designed language 
this line needs to be a compile-time error, because p can be 
null, while r can't be null:

int& r = *p;

The language has to force you to initialize the reference with 
something that is valid.

Bye,
bearophile