Using Boost 1_33_1 and Visual Studio 8. Any and all help appreciated..... Working with "The FlySwapper" example in the "C++ Template Metaprogramming" book. Pages 22-24. It crashes when I do this: std::vector<bool>::iterator i1; std::vector<bool>::iterator i2; use_swap( &i1, &i2 ) // crash here All other types I try work fine. But doing <bool> crashes on this line: iter_swap_impl<use_swap>::do_it(*i1,*i2); // ouch!!! Debug looks like it stopped somewere within vector debug during boost::apply processing. // Fly Swapper code ..... <snip> template <bool use_swap> struct iter_swap_impl; template < class ForwardIterator1, class ForwardIterator2 > void iter_swap(ForwardIterator1 i1, ForwardIterator2 i2 ) { typedef std::iterator_traits< ForwardIterator1 > traits1; typedef typename traits1::value_type v1; typedef typename traits1::reference r1; typedef std::iterator_traits< ForwardIterator2 > traits2; typedef typename traits2::value_type v2; typedef typename traits2::reference r2; bool const use_swap = boost::is_same<v1, v2>::value && boost::is_reference<r1>::value && boost::is_reference<r2>::value; iter_swap_impl<use_swap>::do_it(*i1,*i2); //***** CRASH CRASH here } template <> struct iter_swap_impl<true> // fast one { template < class ForwardIterator1, class ForwardIterator2 > static void do_it( ForwardIterator1 i1, ForwardIterator2 i2 ) { std::cout << "use_swap is TRUE" << std::endl; } }; template<> struct iter_swap_impl<false> { template < class ForwardIterator1, class ForwardIterator2 > static void do_it( ForwardIterator1 i1, ForwardIterator2 i2 ) { std::cout << "use_swap is FALSE" << std::endl; } }; </snip>