I think everybody who uses smartpointers has encountered something like
this:
struct A{};
struct B : A{};
struct C : B{};
void f(shared_ptr<A> const &);
void f(shared_ptr<B> const &);
.
shared_ptr<C> c;
f(c);  //ambigous call


do you consider this a problem worth addressing with a language extension?
a smart pointer clearly behaves unlike an ordinary pointer here.
a widely used used smart pointer it now part of TR1 and I think you
can't solve this with current language features.

Regards,

---
[ comp.std.c++ is moderated.  To submit articles, try just posting with ]
[ your news-reader.  If that fails, use mailto:std-c++@ncar.ucar.edu    ]
[              --- Please see the FAQ before posting. ---               ]
[ FAQ: http://www.jamesd.demon.co.uk/csc/faq.html                       ]