Re: Re:

[Krzesimir Nowak <qdlacz gmail com>]

2011/1/28 Culpian Camilo Martin <camiloculpian gmail com>:
> El vie, 28-01-2011 a las 14:46 +0100, Krzesimir Nowak escribió:
>> 2011/1/28 Culpian Camilo Martin <camiloculpian gmail com>:
>> > ok, i'll try it, i have had some troubles doing this:
>> >
>> > class foo
>> > {
>> >        static ref_ptr<foo> create
>> >        (
>> >                return ref_ptr<foo>(new foo());
>> >        );
>> >        foo();
>> >        ~foo();
>> >        ref_ptr<foo> set_something()
>> >        {
>> >                //set something
>> >
>> >                return ref_ptr<foo>(this);
>> >                //for using foo->set_something()->set_something();
>> >                // oviously the ref_ptr delete "this", and cause a segfault
>> >                // any idea how can avoid this?
>> >        }
>> > }
>>
>> Would be good to show what is this ref_ptr class...
>>
>> If the below code segfaults then maybe copy constructor of ref_ptr
>> does not increment reference count.
>>
>> ref_ptr<foo> f = foo::create();
>> f->set_something()->set_something();
>
> the problem is not when i do this:
>
> ref_ptr<foo> f = foo::create();
> f->set_something()->set_something();
>
> the problem is when i do this:
>
> class foo_b : public foo
> {
>        static ref_ptr<foo_b> create()
>        {
>                return ref_ptr<foo_b>(new foo_b());
>        }
>        foo_b();
>        ~foo_b();
> }
>
> when i do:
>
> foo_b foob = foo_b::create();
> foob->set_something(); //here ref_ptr delete the object member class
> foo... this is what i can't do right.

Now I see. An option would be:
1. returning void instead of ref_ptr to this.
2. coding the reference count inside foo_b, instead of in ref_ptr.

I would opt for first solution.