Re: [boost] C++03 unique_ptr emulation

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