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From: Olaf van der Spek <olafvdspek@gmail.com>
Newsgroups: gmane.comp.lang.c++.isocpp.proposals
Subject: Re: optional<T>, one more value or two states
Date: Mon, 28 Jan 2013 11:08:05 +0100
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On Mon, Jan 28, 2013 at 10:07 AM, Daniel James <dnljms@gmail.com> wrote:
> On 27 January 2013 21:39, Olaf van der Spek <olafvdspek@gmail.com> wrote:
>> On Sun, Jan 27, 2013 at 9:27 PM, Daniel James <dnljms@gmail.com> wrote:
>>> But it could easily be changed to meet them. 'Optional' is a container
>>> (in the wider sense) with a maximum of 1 element. It is not in any
>>> sense a pointer. In fact, std::optional probably should meet the basic
>>> container requirements, as it would allow it to be used with generic
>>> functions.
>>
>> It's a bit like static_vector with max_size 1, true. Though I'm not
>> sure what supporting a container interface really buys you.
>
> It depends on how well the range algorithms works out. They might
> provide a more elegant way to manipulate optionals than if statements,
> similar to how a range algorithm can be more elegant than a for loop.
> This has worked out well in other languages, for example in Scala:

Wouldn't this be better handled by a wrapper that allows optionals,
(smart) pointers and references to be handled as ranges?
Separation of concerns says this shouldn't be handled by optional itself.



-- 
Olaf

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