Re: [Boost-bugs] [Boost C++ Libraries] #5127: Incorrect result_of usage in transform_iterator

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #5127: Incorrect result_of usage in transform_iterator
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-08-18 21:16:47

#5127: Incorrect result_of usage in transform_iterator
--------------------------------------+-------------------------------------
  Reporter:  mimomorin@…              |       Owner:  dave              
      Type:  Patches                  |      Status:  closed            
 Milestone:  Boost 1.47.0             |   Component:  iterator          
   Version:  Boost Development Trunk  |    Severity:  Problem           
Resolution:  fixed                    |    Keywords:  transform_iterator
--------------------------------------+-------------------------------------

Comment (by TLBettens@…):

 == Warning message introduced into release 1_50_0 ==

 This change went into release 1-50_0 and now causes a warning message to
 be emitted in Visual C++ version 10, perhaps others versions as well.

 Compiler warning message:

 {{{
 2>c:\boostbuilding\boost_1_50_0\boost\iterator\transform_iterator.hpp(49):
 warning C4180: qualifier applied to function type has no meaning; ignored
 2>
 c:\boostbuilding\boost_1_50_0\boost\iterator\transform_iterator.hpp(70) :
 see reference to class template instantiation
 'boost::detail::transform_iterator_base<UnaryFunc,Iterator,Reference,Value>'
 being compiled
 }}}

 Workaround is to either revert back to release 1_49_0 by removing the
 '''const''':

 {{{
 boost::result_of</*const*/ UnaryFunction(Iterator::reference)>
 }}}

 , or disable the warning message using something like:

 {{{
         #if defined(BOOST_MSVC)
         #   pragma warning (push)
         #   pragma warning (disable:4180) // warning C4180: qualifier
 applied to function type has no meaning; ignored
         #endif
           typedef typename ia_dflt_help<
               Reference
             , result_of<const UnaryFunc(typename
 std::iterator_traits<Iterator>::reference)>
           >::type reference;
         #if defined(BOOST_MSVC)
         #   pragma warning (pop)
         #endif

 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5127#comment:7>
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