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

John Maddock wrote:

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Do we have to use Typeof in common_type at all? In the cases in which common_type::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?

Yes, it's not as I specified. The proper procedure for ?: is actually - if T and U are the same type, T - if T or U is a class type - if T converts to U and U does not convert to T, U - if U converts to T and T does not convert to U, T - otherwise error - if T and U are arithmetic or enumerations, "usual arithmetic conversions" - if T and U are pointers, "composite pointer type" There's no need for typeof anywhere, as far as I can see.

In any case this is basically what happens when BOOST_COMMON_TYPE_DONT_USE_TYPEOF and BOOST_NO_CXX11_DECLTYPE are set.

I'll take a look.