From: Howard Hinnant (hinnant_at_[hidden])
Date: 2006-11-29 10:51:38
On Nov 29, 2006, at 10:33 AM, Richard Hadsell wrote:
> David Klein wrote:
>
>> so are there any objections about adding this feature to scoped_ptr?
>>
>>
> I'm sure I have seen this discussion before. I believe the issue was
> the size of scoped_ptr itself. It is supposed to be a lightweight
> object, no bigger than the pointer it holds. Any added overhead is
> unacceptable. If you can implement the feature without adding any
> data
> members, fine. Otherwise, please create a new class.
<nod> This comes up now and then.
Fwiw, anyone/everyone is welcome to my emulation of the proposed C+
+0X unique_ptr:
http://home.twcny.rr.com/hinnant/cpp_extensions/unique_ptr_03.html
Sorry, it isn't documented. Here's the best documentation I
currently have:
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/
n1856.html#Addition%20-%20Class%20template%20unqiue_ptr
The (non)copyright at the top means you can do whatever you want with
the code, including stripping my name out of it.
In a nutshell:
* It has a deleter.
* If the deleter is an empty class, sizeof(unique_ptr<T, D>) ==
sizeof(T*).
* It has unique ownership semantics like auto_ptr/scoped_ptr.
* It does not transfer ownership with copy syntax (modulo a bug
mentioned in the source code).
* It has cute syntax to safely handle arrays: unique_ptr<T[]>.
* You can also customize the storage type (defaults to T*) by giving
your deleter an optional D::pointer type.
* The deleter can be a reference to a deleter. The sizeof the
unique_ptr swells by a word when you do this, but it does come in
handy when you want to reference some other deleter instead of copy
it in to the unique_ptr.
* The deleter can be a function pointer. sizeof swells here too.
* It has been proposed for standardization.
-Howard