Boost logo

Boost :

From: Fernando Cacciola (fernando_cacciola_at_[hidden])
Date: 2005-10-11 12:28:30

Howard Hinnant wrote:
> On Oct 10, 2005, at 10:36 AM, Fernando Cacciola wrote:
>> Hi people,
>> Not only I wasn't there at the mettings but from Thuesday night I was
>> undergoing an emergency gall bladder surgery so I coulnd't even
>> respond the
>> email.
>> But I'm back home now... still recovering but I can sit in front of
>> the notebook :)
> Wow, I surely hope you recover fast.
Thank you!

>>> Optional : Interested? Strong yes 9, weak yes 2, weak no 3,
>>> strong no 0 Significant concerns about the interface:
>>> Pointer interface.
>> It figues. FWIW, I'll stand strong on this part of the interface...
>> though
>> I'm not sure how much my position can affect the final TR2 form.
>>> Two ways of doing the same thing.
>> Hmm, really? Did they gave examples?
> I believe this refers to the pointer interface plus get().
Oh.. what is get() doing there? ;)

>>> Depends on nullptr - is there a backup plan.
>> I could have proposed 'none' along Optional, in its own context, but
>> that
>> would duplicate much of nullptr... I didn't see the need for such
>> duplication.
>>> Dubious of use of references.
>> Does this mean they don't see that as useful or that is not well
>> supported?
> I believe there was specific concern about reference rebinding under
> optional<T&>. There were also several comments that went like: I use
> optional all the time (gives use case), but I've never needed to use
> it
> with reference types.

Hmm, well, as I'll explain in the response to Joel the "normal" semantics
for references are even more troubled; but I see how this can be an endless

>> General question: what shall I do from now on? Follow the discussions
>> on
>> comp.std.c++?
> This is a good question, and I can only give an opinion (as opposed to
> an authoritative answer).
> You might explore a interface here on boost which did not have the
> pointer interface, and which dropped reference support. Then perhaps
> submit a follow on paper reflecting that experience. Said paper may
> either modify your current proposal, or more fully support it.
Well, I can certainly code up a, say, nullable<> type to explore other
interface choices; but I'm unsure how to get proper feedback. Boost.Optional
has been here for a while now, yet apart from the detailed feedback of just
a couple of users, all I know is that people use it; but that's it... I
don't get to see how much do they like/diskike this and that of the
So, how could I eventually compare the pros/cons of both interfaces?

..maybe I should post a "call for public report on optional" or so...


Fernando Cacciola

Boost list run by bdawes at, gregod at, cpdaniel at, john at