Hi, I am trying to convert a boost::array into a fusion::vector. reinterpreting the memory from boost::array. It works for tuples but not fusion::vector, why is that. Is there a way to make it work? ( I was hoping that the memory layout is the same to make conversion from one to the other very easy.) #include <boost/fusion/container.hpp> #include <boost/fusion/include/container.hpp> #include<boost/array.hpp> #include<iostream> #include<boost/tuple/tuple.hpp> using std::clog; using std::endl; int main(){ boost::array<double, 3> ba={{1.0, 2.1, 3.2}}; clog << "ba: " << ba[0] << ", " << ba[1] << ", " << ba[2] << endl; using namespace boost::fusion; vector<double, double, double> bfv( reinterpret_cast<vector<double, double, double>&>(ba) ); //doesn't work as expected clog << "bfv: " << at_c<0>(bfv) << ", "<< at_c<1>(bfv) << ", " << at_c<2>(bfv) << endl; using boost::tuple; tuple<double, double, double> btt(reinterpret_cast<tuple<double, double, double>&>(ba) ); // works! clog << "btt: " << btt.get<0>() << ", "<< (btt).get<1>() << ", " << (btt).get<2>() << endl; return 0; } outputs: ba: 1, 2.1, 3.2 //original data bfv: -9.25597e+61, -2.35344e-185, 4.87507e-270 //not expected btt: 1, 2.1, 3.2 //works! Let me give some context, the reason I am doing this is that I need to interface fusion::vector of boost::quantities (all have the sizeof double) and adimensionalize the list of quantities into an array of doubles and vise-versa In reality, the final goal is to get this to work: boost::array<double, 3> ba={{1.0, 2.1, 3.2}}; vector<quantity<si::length>, quantity<si::time> , quantity<si::mass> > bfv( reinterpret_cast<vector<quantity<si::length>, quantity<si::time> , quantity<si::mass> >&>(ba) ); (or other generic option to go from array<double, N> to vector<quantity<T1>, quantity<T2>, ... quantity<TN> >) but since I can't make it work with simple 'doubles' I am asking why this could be done. Thank you again, Alfredo