Re: [Boost-users] shared_ptr and inheritance of the raw pointer

From: Nat Goodspeed (ngoodspeed_at_[hidden])
Date: 2006-07-26 07:51:07

> -----Original Message-----
> From: boost-users-bounces_at_[hidden] [mailto:boost-users-
> bounces_at_[hidden]] On Behalf Of Yossi.Itzkovich_at_[hidden]
> Sent: Wednesday, July 26, 2006 3:03 AM
> To: boost-users_at_[hidden]
> Subject: [Boost-users] shared_ptr and inheritance of the raw pointer
> 
> I have this code:
> 
> #include <boost/shared_ptr.hpp>
> 
> class A{ // base class
> public:
    virtual ~A();   // otherwise A isn't polymorphic, can't downcast
> };
> 
> class B : public A{
> public:
>   int b1;
> };
> 
> typedef boost::shared_ptr<A> tSmartA;
> typedef boost::shared_ptr<B> tSmartB;
> 
> void foo (const tSmartB& smartOne);  // need ; for syntax
            ^^^^^ permits passing an expression
> 
> int main () {
>   tSmartA a(new B);
    foo(boost::dynamic_pointer_cast<B>(a));
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>   return 0;
> }
> 
> 
> How can I then send a to foo()  ?

[Nat] With the three changed lines shown above, this compiles for me
under MSVC 7.1.