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Subject: Re: [boost] [optional] Safe optional
From: Andrzej Krzemienski (akrzemi1_at_[hidden])
Date: 2014-11-20 04:18:32

2014-11-19 22:08 GMT+01:00 Nevin Liber <nevin_at_[hidden]>:

> On 19 November 2014 13:42, Andrey Semashev <andrey.semashev_at_[hidden]>
> wrote:
> > I think you're taking it too negatively.
> Perhaps. Maybe it's just the scars from trying to get optional into C++14.
> Whenever expected or variant gets discussed in committee, the question of
> "Do we still need optional?" gets raised. The answer in favor of optional
> is yes because it has a much better interface. If the interface is in
> flux, well, that argument isn't very compelling.
> While I will continue to vote strongly in favor of adding optional to
> C++17, I might not participate in the battles to help make that happen,
> since I am far more interested in forward progress than churn for churn's
> sake. But that is just me.

Hi Nevin. I really appreciate what you are saying. You made me realize one
thing I was not aware before. That an ordinary programmer expressing his
ideas and opinions on a forum, can affect what gets and what does not get
into the standard. I am not being sarcastic.

Proposing Optional was a pain even for me, even though I am not exposed to
the process. I appreciate your efforts in helping Optional get into the
standard. I can also see why this thread can be seen as undermining the

I am pretty sure Optional will make it into the standard. Its advantage
over Variant or Expected is that it is already there in a TS and that it
proved useful for more than a decade. A working solution is better than a
projected future solution. Back in around 2009, I was wondering why they
are adding type traits when at the same time all the primitive concepts
like CopyConstructible were being added. It looked like an unnecessary
duplication. But their advantage was that they were real, unlike concepts.

Best regards,

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