[boost] Re: shared_pointer for C-allocated object?

From: Larry Evans (cppljevans_at_[hidden])
Date: 2004-02-02 19:12:17

On 02/02/2004 10:32 AM, Javier Estrada wrote:
>>Custom deleters are your friend.
> 
> 
> How about custom allocators AND deleters?
> 
> The reason I say this is because it would be useful to have a policy-based
> approach when interacting with APIs that do the allocation/destruction.
But instead of placing two pointers(1 for allocator + 1 for deleter) why
not use a virtual function table for both?  In other words, instead of
just having a sp_counted_base::dispose + destruct, why not add an
virtual allocate?  Then, instead of passing the deleter as an argument
to the CTOR, a sp_counted_base* would be passed and the user would
define a subclass of sp_counted_base which used whatever allocator
and destructor desired.  This would save some memory and wouldn't
(I don't think) constrain the user much since I don't think the user
would want a separate destructor and allocator for each instance of
the shared object.