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

Subject: Re: [boost] [variant] Please vote for behavior
From: Dave Abrahams (dave_at_[hidden])
Date: 2013-01-30 11:18:07

on Mon Jan 28 2013, Gottlob Frege <gottlobfrege-AT-gmail.com> wrote:

> On Mon, Jan 28, 2013 at 4:47 PM, Joel de Guzman <djowel_at_[hidden]> wrote:
>
>> On 1/29/13 5:06 AM, Gottlob Frege wrote:
>>
>>> On Mon, Jan 28, 2013 at 1:35 PM, Joel de Guzman <djowel_at_[hidden]> wrote
>>>
>>>>
>>>>
>>>>  No. It's still just operator(T const&). You can't use a "singular
>>>
>>>> valued" recursive_wrapper in any other operation apart from assignment,
>>>> destruction or move.
>>>>
>>>>
>>>
>>> How do I know if is it singular valued?
>>>
>>
>> How do you know if an iterator is singular valued? You can't. Same here.
>>
>>
> it == container.end()?
>
> Or am I confused?

Yes, you are.  That's not singular; it's a past-the-end iterator.  You
can still do comparisons against a past-the-end iterator, but not with a
singular one.

-- 
Dave Abrahams
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