[Boost-bugs] [Boost C++ Libraries] #13012: boost::has_equal_to fails with captureless lambda expression types

Subject: [Boost-bugs] [Boost C++ Libraries] #13012: boost::has_equal_to fails with captureless lambda expression types
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2017-05-06 09:41:11

#13012: boost::has_equal_to fails with captureless lambda expression types
------------------------------+-------------------------
 Reporter:  joaquin           |      Owner:  johnmaddock
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  type_traits
  Version:  Boost 1.63.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+-------------------------
 The following

 {{{
 include <boost/type_traits/has_equal_to.hpp>

 int main()
 {
   auto f=[](){};
   (void)boost::has_equal_to<decltype(f)>::value;
 }
 }}}

 generates a compile time error about an ambiguity for `operator==`, see
 [http://coliru.stacked-crooked.com/a/f1010ec991d2721a]. The problem has
 been tested to show in GCC and VS2015. For what it's worth, capturing
 lambda expressions do not trigger the problem.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/13012>
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