Re: [boost] Loki SmartPtr questions

From: Gustavo Guerra (gustavobt_at_[hidden])
Date: 2002-01-15 18:04:36

[Peter Dimov]
> As for release(), I think that it needs to be dropped.

[Robert Stewart]
> I recently created a special-purpose smart pointer that releases the ref
> count of something relying on a C API. I wanted to write my functions that
> return such pointers to return smart pointer objects to ensure that the
ref
> count was decreased even if I simply ignored the return value of such
> functions. However, when returning to the calling C API, I needed to turn
> over the raw pointer in the return value, relinquishing ownership of it.
To
> do that, I call release() on my smart pointer class (which, based upon
> Andrei's insight, should be a non-member function).
>
> If I were using a Boost smart pointer without support for release(), how
> would I relinquish ownership()? That is, how do I tell the Boost smart
> pointer to not "deallocate" the pointer it holds, without release()?
>

After reading
http://groups.google.com/groups?q=g:thl1602934015d&hl=en&selm=3C3990CE.93B75
728%40oxyware.com
I had this idea.

Why don't we drop get and release and instead put something like this:

template<T>
class shared_ptr
{
private:
  T* ptr;
public:
  template<class F>
  void call_legacy_function(F callback)
  {
    callback(ptr);
  }
};

Of course the callback could still do something bad with the pointer, but
it's more localized.

Just and idea
Gustavo Guerra