Idiomatic use of std::auto_ptr or only use shared_ptr?

Question

Now that shared_ptr is in tr1, what do you think should happen to the use of std::auto_ptr? They both have different use cases, but all use cases of

Answer 1

To provide a little more ammunition to the 'avoid std::auto_ptr' camp: auto_ptr is being deprecated in the next standard (C++0x). I think this alone is good enough ammunition for any argument to use something else.

However, as Konrad Rudolph mentioned, the default replacement for auto_ptr should probably be boost::scoped_ptr. The semantics of scoped_ptr more closely match those of auto_ptr and it is intended for similar uses. The next C++09 standard will have something similar called unique_ptr.

However, using shared_ptr anywhere that scoped_ptr should be used will not break anything, it'll just add a very slight bit of inefficiency to deal with the reference count if the object is never actually going to be shared. So for private member pointers that will never be handed out to another object - use scoped_ptr. If the pointer will be handed out to something else (this includes using them in containers or if all you want to do is transfer ownership and not keep or share it) - use shared_ptr.