Re: [boost] [result_of] fails with clan (C++11)

Subject: Re: [boost] [result_of] fails with clan (C++11)
From: Jeffrey Lee Hellrung, Jr. (jeffrey.hellrung_at_[hidden])
Date: 2012-11-27 15:56:36

On Tue, Nov 27, 2012 at 12:47 PM, Oliver Kowalke
<oliver.kowalke_at_[hidden]>wrote:

> Hello,
> clang (c++11 support) fails on code like:
>
> BOOST_STATIC_ASSERT((
>             is_same< void, typename result_of< Fn() >::type >::value));
>
> with error:
>
>  no type named 'type' in 'boost::result_of<void (&())(X &)>'
>             is_same< void, typename result_of< Fn() >::type >::value));
>                            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~**~~
>

Does Fn == void (&)(X&) or void (X&) ? I.e., is it a unary function type?

There might've been a recent change only for Clang to allow result_of to be
better usable with SFINAE: result_of< F ( Args... ) > doesn't have a nested
type typedef if F ( Args... ) is ill-formed (which appears to be the case
here).

../boost/static_assert.hpp:48:**50: note: expanded from macro
> 'BOOST_STATIC_ASSERT'
> #  define BOOST_STATIC_ASSERT( B ) static_assert(B, #B)
>                                                  ^
>
>
> Do you know why it fails? (other compilers like gcc, intel, msvc compile
> the code)
>

- Jeff