clear_policy.cc

#include <type_traits>
#include <iostream>

template <bool isPod = true>
class FooClearPolicy {
public:
  static void clear() {
    std::cout<<"pod clear"<<std::endl;
  }
};

template <>
class FooClearPolicy<false> {
public:
  static void clear() {
    std::cout<<"non-pod clear"<<std::endl;
  }
};

template <typename T, typename ClearPolicy = FooClearPolicy<std::is_pod<T>::value>>
class Foo {
public:
  void clear() {
    ClearPolicy::clear();
  }
};

template<typename T>
class Goo {
  typedef Foo<T> impl;
};

class Bar {
public:
  Bar() = default;
  Bar(const Bar& rhs) {}
};

int main ()
{
  Foo<int> f;
  Foo<Bar> g;

  f.clear();
  g.clear();
  return 0;
}