DIP74: Reference Counted Class Objects

[Volodymyr via Digitalmars-d]

On Tuesday, 3 March 2015 at 09:58:12 UTC, Andrei Alexandrescu 
wrote:
> On 3/3/15 12:53 AM, Volodymyr wrote:
>> On Thursday, 26 February 2015 at 21:50:56 UTC, Andrei 
>> Alexandrescu wrote:
>>> http://wiki.dlang.org/DIP74 got to reviewable form. Please 
>>> destroy and
>>> discuss.
>>>
>>> Thanks,
>>>
>>> Andrei
>>
>> With opAddRef/opRelease class does respondible for its 
>> dealocation and
>> its own payload so breaks SOLID's single responsibility 
>> principle.
>
> Correct. That's a tactical matter that can be addressed e.g. 
> with mixin templates.
>
>> As
>> for me better design will be to do it closer to C++'s 
>> shared_ptr.
>> e.g:
>>
>> // maybe with @arc
>> struct RefCounter(T)
>> {
>> void opAddRef();
>> void opRelease();
>> ref T obj;
>> ref size_t count;
>> }
>> }
>>
>> RefCounter!Widged myRefToWidget;
>>
>> RefCounter with default ctor/dtor. opAddRef and opRelease is 
>> for
>> compiler optimtimisation and elimination of redunadant ref 
>> counter
>> increment/decrement.
>
> We couldn't make that work with safety.
>
>
> Andrei

Why couldn't? Let's for all @return (this) functions make 
wrappers that rerturn RefCounter!MemberType(member, 
ownerCounterPtr), and same thing for public fields

The wrapper nedded only for realy owned resources (but not simple 
gc's refs).