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

Hi, I have this code: #include <boost/shared_ptr.hpp> class A{ // base class public: }; class B : public A{ public: int b1; }; typedef boost::shared_ptr<A> tSmartA; typedef boost::shared_ptr<B> tSmartB; void foo (tSmartB& smartOne) // should get a pointer to derived { } int main () { tSmartA a(new B); foo(a); // This line doesn't compile because foo expects to get tSmartB return 0; } How can I then send a to foo() ? Thanks Yossi