Re: [Boost-users] shared_ptr<> null deleter

From: Noah Roberts (roberts.noah_at_[hidden])
Date: 2008-05-16 11:49:44

Kevin Martin wrote:
> I have just discovered to my delight that you can use shared_ptr with  
> a null deleter to pass around stack based objects. This is great  
> because a function shouldn't care whether a parameter passed to it is  
> on the heap or stack. So I can write general functions to accept a  
> shared_ptr and if I have to pass a stack based object I can just pass  
> a null deleter.

You can do a lot more than that!  Consider the case of a handle of some 
sort that you need to return to a service when you are done.  Case in 
point, in order to get rid of an sqlite database connection pointer you 
call db_close(), NOT delete.

No big deal, just use db_close as your deleter!

The fact that you can use anything as a deleter for a shared_ptr turns 
it into a hammer with a driver head.  So then everything IS effectively 
a nail.