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Subject: Re: [boost] [outcome] Second high level summary of review feedback accepted so far
From: Niall Douglas (s_sourceforge_at_[hidden])
Date: 2017-05-30 17:53:25

On 30/05/2017 18:43, Peter Dimov via Boost wrote:
> Niall Douglas wrote:
>> Do you accept that the static checked and runtime checked varieties
>> are orthogonal user bases? There is a camp of users who strongly
>> prefer no runtime overhead and static checking.
> Why are their needs not served by value_if?
> auto r = function();
> if( auto* p = r.value_if() )
> {
> // use *p
> // no runtime overhead on using *p
> // static checkers know use of *p implies p != nullptr
> }
> Between this pattern and using `assert( r.has_value() )` directly to
> advise the static checker, are we not covered?

I'm still pondering your idea on this for the runtime checked editions.
So far I am liking it, but I need to sleep on it some more.

But there was still a large minority of folk who want all-narrow
observers. They haven't voiced anything to say they have changed their

I currently, roughly speaking, find approx 50% in favour of a runtime
checked edition, approx 40% in favour of a statically checked edition.

Emil and Vicente make up the 10% of folk who want something completely


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