Re: Multiple inheritance and enable_shared_from_this

From: Jason Winnebeck (yg-boost-users_at_[hidden])
Date: 2003-07-19 21:31:51

No Russel I just tried that, it won't work.  That's sort of how my code 
was.  Your TheBase class is my SharedThis class from eariler example, 
and I had non-templated.  It wouldn't compile because the 
enable_shared_from_this couldn't cast some pointer.

Jason

Russell Hind wrote:
> Jason Winnebeck wrote:
> 
> 
>>I tried using enable_shared_from_this with virtual inheritance, just to 
>>see if it would work.  I couldn't get it to work.  The first barrier is 
>>that enable_shared_from_this is a templated class, and from what I 
>>understand is that two template instantiations of a class are two 
>>entirely different classes, so I didn't even try to use virtual on that.
>>
> 
> 
> Sorry, I completely missed that enable_shared_from_this was a template 
> class.  Yes in that case it won't work unless possibly you did something 
> like this
> 
> class TheBase : public enable_shared_from_this<TheBase>
> {
> };
> 
> class Base1 : virtual public TheBase
> {
> };
> 
> class Base2 : virtual public TheBase
> {
> };
> 
> class MyClass : public Base1, public Base2
> {
> };
> 
> But then you may need dynamic_casts somewhere to get the actual 
> interface pointer you required later so don't know if that will be possible.
> 
> Thanks
> 
> Russell