Which is the correct type trait to use to check if an element of type T can be assigned to an element of type U. Is it any of the following: boost::is_convertible<T, U> std::is_assignable<U, T> Now boost::is_convertible<double, int>::value is true while std::is_assignable<int, double>::value is false. What does this signify? -- Aaron Levy aaron.levy@yandex.com