From: Peter Dimov (pdimov_at_[hidden])
Date: 2002-04-20 05:56:58
From: "Fernando Cacciola" <fcacciola_at_[hidden]>
> I wonder if this could be confusing: shared_ptr uses a detached or
intrusive
> count depending on how it is constructed.... I find more intuitive to
expect
> that shared_ptr uses a detached or intrusive count depending on the
pointee
> type, regardless of how you create it.
Let's assume that shared_ptr autodetects. Consider my original example:
// some member function
shared_ptr<this_type> f()
{
return shared_ptr<this_type>(this);
}
Is this correct? Yes, if this_type is derived from counted_base, undefined
behavior otherwise.
Now consider the explicit version:
// some member function
shared_ptr<this_type> f()
{
return intrusive_ptr<this_type>(this);
}
Now the compiler can verify the correctness.
It's always better when the correctness of the code can be determined
without context.