Re: [boost] [optional] problems with swap()

From: vicente.botet (vicente.botet_at_[hidden])
Date: 2008-04-10 17:44:19

From: "Niels Dekker - mail address until 2008-12-31" 
<nd_mail_address_valid_until_2008-12-31_at_[hidden]>
Subject: Re: [boost] [optional] problems with swap()

> Thorsten Ottosen wrote:
<snip>

> What would you think of having boost::optional implemented by holding a
> pointer to T, instead of an aligned_storage object and a m_initialized
> flag?  It would manage the memory that the pointer would point to.
> Having NULL would indicate being uninitialized. (I admit it's a rather
> theoretical question, because I don't even know if Fernando would like
> such an approach...)

I don't think that it is a good idea to have a pointer, I expect no extra 
allocation from optional.
You can always try to do that in another class, optional_ptr or whatever 
name you want for.
I think that this class will be very eassy to implement. Still I will expect 
value semantics, and in this
case the extra allocation on copy constructors and assignations will be very 
inefficient.

Best
_____________________
Vicente Juan Botet Escriba