Re: [boost] [variant] Please vote for behavior

Subject: Re: [boost] [variant] Please vote for behavior
From: Dave Abrahams (dave_at_[hidden])
Date: 2013-02-01 09:57:14

on Thu Jan 31 2013, Paul Smith <pl.smith.mail-AT-gmail.com> wrote:

> On Thu, Jan 31, 2013 at 10:11 PM, Dave Abrahams <dave_at_[hidden]> wrote:
>>
>> on Thu Jan 31 2013, Paul Smith <pl.smith.mail-AT-gmail.com> wrote:
>>
>>> On Thu, Jan 31, 2013 at 3:22 AM, Dave Abrahams <dave_at_[hidden]> wrote:
>>>>
>
>>>> on Mon Jan 28 2013, Paul Smith <pl.smith.mail-AT-gmail.com> wrote:
>>>>
>>>>> This issue has been discussed more than once before, and nothing I say
>>>>> here is my own opinion, so please don't take it out on me.
>>>
>>>>> For example, see N3264 (CH-18 and US-85: Clarifying the state of
>>>>> moved-from objects (Revision 1)):
>>>>>
>>>>> http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3264.htm
>>>>>
>>>>>> and Dave confirms that,
>>>>>
>>>>> I don't want to read into what Dave said too much, because he's here
>>>>> and he can clarify it. But I believe what he said is that specific
>>>>> algorithms, in their own localized context, practically only require
>>>>> destructibility and assignability. And even then,
>>
>> I was disavowing this part because I don't claim to know it for sure:
>>
>>>>> it's not something the standard actually guarantees in general,
>>>>> though, and the requirements are still much stricter, perhaps
>>>>> superfluously so.
>>
>> and I was disavowing this part because I disagree with it:
>>
>>>>> it's a good selling point for having destructive move semantics -
>>>>
>>>> That doesn't sound like anything I meant to say, but I do agree fully
>>>> with the resolutions (if not the NB comments) in the paper cited above.
>>>
>>> Then what did you mean?
>>
>> See above.
>
> Actually, that's not really what I asked. Joel asked you if
> destructibility and assignability is all the standard library needs
> from moved-from objects. You responded: "That's all the standard
> library will use." 

Yes.

> Now you seem to say the opposite. 

Where?

> I think this was a source of confusion :-)

I can imagine it would be.

-- 
Dave Abrahams
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