id summary reporter owner description type status milestone component version severity resolution keywords cc 8188 boost/type_traits.hpp should define 'conditional' in c++ 2011. edupuis John Maddock "From a message posted on the Boost mailing list on February 27. Template boost::conditional is defined by {{{ #include ""boost/type_traits/conditional.cpp"" }}} Indeed, type_traits accepted in TR1 did not included 'conditional'. However, C++2011 adds it, hence it is expected that when compiling in C++2011 mode, the following include {{{ #include ""boost/type_traits.hpp"" }}} would indeed define 'conditional' (by including conditional.hpp for example). " Bugs closed To Be Determined type_traits Boost 1.53.0 Problem worksforme