Re: [boost] [smart-ptr] Custom deallocator for scoped_ptr

From: Peter Dimov (pdimov_at_[hidden])
Date: 2003-04-03 05:04:31

Lars Gullik Bjønnes wrote:
> We find ourselves in want of a custom deallocator for scoped_ptr, but
> no such thing seems to exist now.
>
> Has this been thought of?
>
> If yes, what was the reason for not supporting this?

If you want a shared_ptr-style runtime custom deallocator support, this is
not supported because the overhead was (and is) considered unacceptable for
scoped_ptr. Use shared_ptr instead.

The alternative is

template< class T, class D = boost::checked_deleter<T> > class scoped_ptr
{
public:

// ...

    ~scoped_ptr() { D()(ptr); }
};

The concern here is that the change may potentially break user code that
uses a template template parameter to pass
scoped_ptr/auto_ptr/shared_ptr/whatever_ptr as an argument.

I'm not yet sure whether the increased functionality justifies breaking such
code. OTOH I'm not sure whether such code even exists. ;-)

So if someone has an opinion about this potential change to scoped_ptr, now
is probably the right time to express it.