#include <boost/mpl/apply.hpp>
#include <boost/mpl/vector.hpp>
#include <boost/mpl/transform.hpp>

using namespace boost::mpl;

struct foo
{
  template <typename T>
  struct apply
  {
    typedef T type;
  };
};

int main()
{
  typedef transform<
    vector<char,int,double>,
    apply1<foo,_1>
  >::type t1;
}