Subject: Re: [boost] C++03 unique_ptr emulation
From: vicente.botet (vicente.botet_at_[hidden])
Date: 2009-01-09 16:54:01
----- Original Message -----
From: "Ion Gaztañaga" <igaztanaga_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Friday, January 09, 2009 9:15 PM
Subject: Re: [boost] C++03 unique_ptr emulation
>
> David Abrahams wrote:
>> So you're saying, in other words, that "move(x)" really means "you have
>> permission to move x" but the one I proposed would mean "move it, now."
>>
>> OK, good point.
>>
>> So what about this horrible little proposal?
>>
>> template <class T>
>> struct rv<T> : T
>> {
>> private:
>> rv();
>> ~rv();
>> rv(rv const&);
>> void operator=(rv const&);
>> };
>>
>> template <class T>
>> boost::enable_if<is_class<T>, rv<T>&>
>> move(T& x)
>> {
>> return static_cast<rv<T>& >(x);
>> }
>>
>> Does that solve any problems?
>
> How can that work? What would you need to add to T? Disable non-const
> copy constructor?
>
>> Yeah, I know it's not theoretically portable, but it should be portable
>> in practice. Especially when it comes to emulating language features, I
>> care less and less about the letter of the law :-)
>
> I would be really interested in this proposal.
Attaced it is your move_test adapted to the new proposal. It works on more cases than before.
Define ALT1to come back to the preceding definition of move and rv.
Thanks,
Vicente