[cfe-dev] ObjC++ and MyObjCClass.class syntax

[Fariborz Jahanian]

On Aug 11, 2010, at 11:11 AM, Jean-Daniel Dupas wrote:

> You can't use class as a property name or as an ivar name in objc++
>
> This extension is just to be able to write for example:
>
> [obj isKindOfClass:NSString.class]
>
> instead of
>
> [obj isKindOfClass:[NSString class]]
>
>
> As the +(Class)class method is defined on NSObject, this syntax may  
> virtually be used by any ObjC class.
>
> I know this syntax is "abusing" the new property syntax as it uses  
> it to call a standard accessor method (not defined as a property),  
> but this kind of "abuse" is supported for all other accessors name  
> and g++ support it for 'class', so it may be worth supporting it too.
>
> Here is a test case accepted by g++ but rejected by clang:
> ---------------------------------
> @interface I {
> int cls;
> }
>
> + (int)class;
>
> @end
>
> @implementation  I
> - (int) Meth { return I.class; }
> @end

I see. Yet g++ rejects a similar case when 'class' is instance method,  
or any other use of 'class' in an objective-c context.
  g++'s behavior is probably an accident of implementation. I am not  
sure if we need to follow this particular g++ behavior.

- Fariborz

>
> ---------------------------------
>
> Le 11 août 2010 à 19:57, Fariborz Jahanian a écrit :
>
>> Can you provide a test case. I see that in this case 'class' is  
>> supported as property name in objective-c mode (but not objective-c+ 
>> +).
>> g++ ObjC++  does not support it either.
>>
>> @interface I
>> {
>> int class;
>> }
>> @property int class;
>> @end
>>
>> @implementation  I
>> - (int) Meth { I* Foo; return Foo.class; }
>> @end
>>
>>
>> % gcc -ObjC++ t.m
>> t.m:3: error: expected identifier before ';' token
>> t.m:5: error: expected identifier before ';' token
>> t.m: In function 'int -[I Meth](I*, objc_selector*)':
>> t.m:9: error: expected unqualified-id before 'class'
>> t.m:9: error: expected ';' before 'class'
>> - Fariborz
>>
>>
>> On Aug 11, 2010, at 9:40 AM, Jean-Daniel Dupas wrote:
>>
>>> Hello,
>>>
>>> I would like to know if it is acceptable to add a special case in  
>>> the parser to support the Foo.class syntax in ObjC++ (where Foo is  
>>> an ObjC class).
>>> This syntax already works in classic ObjC, and is supported by GCC  
>>> in both ObjC and ObjC++. But actually, clang does not support it.
>>>
>>> Thanks
>>> <Class.class.patch>
>>>
>>>
>>> -- Jean-Daniel
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> cfe-dev mailing list
>>> cfe-dev at cs.uiuc.edu
>>> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev
>>
>
> -- Jean-Daniel
>
>
>
>