stl_container_trait.h

template<typename T>
struct HasConstIterator {
 private:
  typedef char Yes;
  typedef struct {
    char array[2];
  } No;

  template<typename C> static Yes Test(typename C::const_iterator*);
  template<typename C> static No Test(...);
 public:
  static const bool value = sizeof(Test<T>(0)) == sizeof(Yes);
  typedef T type;
};

template<typename T>
struct IsContainer : std::integral_constant<bool, HasConstIterator<T>::value> {
};