Re: [boost] [config][mpl][type_traits][integer] BOOST_STATIC_CONSTANT should use constexpr

Subject: Re: [boost] [config][mpl][type_traits][integer] BOOST_STATIC_CONSTANT should use constexpr
From: John Maddock (boost.regex_at_[hidden])
Date: 2013-04-22 13:02:22

>Even if most of the uses of integral_constant is to use its member ::value 
>integral constant defines also the operator(), so it is a nullary functor.

OK, but we can add that now without changing BOOST_STATIC_CONSTANT.

>The last sentence will not compile if the operator() is not a constexpr and 
>it can not be a constexpr if ::value is not a consexpr, or can it?

Sure it can, the member value is an interal-constant-expression however we 
define it so it can be used in all constexpr functions.

John.