Re: [boost] [optional] Regression in develop

Subject: Re: [boost] [optional] Regression in develop
From: Andrzej Krzemienski (akrzemi1_at_[hidden])
Date: 2017-10-30 09:44:33

2017-10-30 10:14 GMT+01:00 Vinnie Falco via Boost <boost_at_[hidden]>:

> On Mon, Oct 30, 2017 at 12:47 AM, Andrzej Krzemienski via Boost
> <boost_at_[hidden]> wrote:
> > The following is a test case in type_traits by Vinnie Falco:
> > https://github.com/boostorg/type_traits/pull/52/commits/
> 9779157a787620d163308afa45cb94ef42391b32
>
> My idea for a fix is to just specialize
> `type_traits::is_default_constructible` for `std::pair<T,U>` where U
> is a built-in type, by returning `is_default_constructible<T>`. This
> solves the problem for Optional, which invokes
> `is_default_constructible` with `std::pair<T, bool>` in this specific
> case.
>
> Disclosure: Peter Dimov doesn't like it.
>

I think I agree with Peter here. What if somebody is using boost::pair?

I think I will take time to detect all the broken compilers using test
matrix and disable the feature on those compilers.

Regards,
&rzej;