From: Andrey Melnikov (melnikov_at_[hidden])
Date: 2005-07-16 12:12:11
Calum Grant wrote:
> Andrey Melnikov wrote:
>>
>>I hate extra dynamic memory allocation even more than I hate extra
>>copies, because the former cannot be optimized out and usually takes
>>more time than 10 extra copies. Well, pool allocators help a lot
>>sometimes, but it's an optimization technology.
>>
>>I like Boost.Optional because it offers a good way to deal with
>>optonality without any extra pointers, memory allocations, special
>>"NULL" values or construction or copy operations . I think it's way
>>different from the concept of smart pointers.
>
>
> But we're talking about private implementation. From a semantic
> perspective, Optional behaves like a smart pointer with a "copy on
> assign" policy. Perhaps there would be fewer howls of disapproval if I
> called it a smart container, not a smart pointer.
It's just a terminology question. Boost.Optional isn't a "pointer". It
isn't an enhanced C pointer, it isn't used like a pointer, it doesn't
use pointers internally. It can be "dereferenced", but it's just a
syntactic feature.
Also it isn't a container in STL sense. It doesn't provides range
interface, iterators etc.
I would call Boost.Optional a proxy.
>
> If an implementation improves a smart container/pointer in this
> circumstance then that's fanstastic.
I don't understand you here.
Andrey