Re: [boost] [type_traits] Big changes in develop

Subject: Re: [boost] [type_traits] Big changes in develop
From: John Maddock (jz.maddock_at_[hidden])
Date: 2015-05-28 08:21:16

> Do we have to use Typeof in common_type at all? In the cases in which 
> common_type<T, U>::type is either T or U, can we not find that out by 
> using two overloads? Is this not good enough?
>
Wouldn't that fail where promotions are involved for example with enum 
types?

In any case this is basically what happens when 
BOOST_COMMON_TYPE_DONT_USE_TYPEOF and BOOST_NO_CXX11_DECLTYPE are set.  
I didn't write this one, so to be honest, I'm not sure what's lost in 
that situation - type registration, better support for older MSVC?

John.