Revised RFC on range design for D2

[Andrei Alexandrescu]

Steven Schveighoffer wrote:
> "Steven Schveighoffer" wrote
>> "Andrei Alexandrescu" wrote
>>>> Not really.  A function symbol by itself is the address of the function. 
>>>> A pointer symbol by itself is the address of the data it points to. 
>>>> It's the same.  I don't think you understood the detail that I stated, 
>>>> 'get address it's pointing to', not 'get address of the pointer'.
>>> I understood very well. Your point is off by a mile, and getting only 
>>> farther. Please understand how you are making an elementary mistake.
>>>
>>> Consider:
>>>
>>> int x;
>>>
>>> Then if I only use "x", I am getting x's value (an lvalue in fact), not 
>>> its address. Now consider:
>>>
>>> int * x;
>>>
>>> Then if I only use "x", I am getting x's value, which is the address of 
>>> an int.
>>>
>>> In neither case is it possible for x and &x to mean the same thing. For 
>>> functions some really weird stuff happens:
>>>
>>> // this is C
>>> #include <assert.h>
>>> void foo() {}
>> How does this make any difference to whether you can call a function 
>> without parentheses or not?  You are arguing that for a function defined 
>> as foo(), foo; should mean call function foo, and I'm arguing that it 
>> should be a syntax error.  Neither of us want the C behavior of evaluating 
>> to the function address.
>>
>> I think &foo should be the proper method of taking the address of a 
>> function, as it is in D.
> 
> This is what happens when you can't explain yourself correctly.  Stop typing 
> your vehement response about how I am an idiot right now :)  I realize my 
> mistake in the statements above.
> 
> I think the problem you cited with how foo is equivalent to &foo in C is 
> bad.  I think we are getting sidetracked here, though.  The point I really 
> want to state is that foo; shouldn't mean calling a function named foo.

"State" is very accurate, because aside from stating the point you bring 
nothing to support it.

> I 
> don't think it should mean the address of the function, although it seems 
> consistent with C pointers (IMO, it seems like &foo shouldn't even compile 
> in C if foo means 'address of foo' already).  &foo sounds correct to me, 
> "address of foo."

No. It does NOT seem and is NOT even remotely consistent with C pointers 
because x is not the same thing as &x for all symbols in C except 
functions. Please work through this with books and test programs and 
all, until you fully understand it. It is important.

> Bottom line, I'm not defending the way C takes addresses of functions, but I 
> think the requirement C has to use parentheses to call functions helps to 
> clarify the intentions of the function author, and makes the code clearer.

I agree, and I'd agree even more if you replaced "think" with "believe". 
I hope you also agree you have brought nothing of significance to 
support your thought/belief, while you have received plenty against.

I also agree that Sergey, Bill, and others did bring up good points in 
support for the required trailing "()". It would be more fertile to 
continue discussing those.


Andrei