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Subject: Re: [SG10] Jacksonville additions
From: Agustín Bergé (agustinberge_at_[hidden])
Date: 2016-03-09 19:30:15


On 3/9/2016 10:12 PM, Nelson, Clark wrote:
> I have made a start at the additions we will need to make to SD-6 to reflect
> the JAX meeting; the result is attached.

I'd like to see a feature-test for LWG2296, "std::addressof should be
constexpr"
(http://wiki.edg.com/pub/Wg21jacksonville/StrawPolls/P0304R0.html).

My use case is similar to that of `optional<T>::operator->`, which is a
constexpr function unless `T` is a user-defined type with overloaded
unary `operator&`. Now that `addressof` is a constexpr function, there's
no longer need for that restriction (I'll submit the corresponding LWG
issue once we have a new draft).

I'd like to be able to provide the same level of constexpr-ness on a
piece of code that still supports C++11:

https://github.com/eggs-cpp/variant/blob/master/include/eggs/variant/detail/visitor.hpp#L186-L218

> I am specifically soliciting comments on everything in the document that
> involves a question mark.

For P0036, "Unary Folds and Empty Parameter Packs", maybe bump
`__cpp_fold_expressions`?

Regards,

-- 
Agustín K-ballo Bergé
http://talesofcpp.fusionfenix.com

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