#include <functional>
using namespace std;

struct SingletonTester
{
  template <typename T>
  bool is_singleton(function<T*()> factory)
  {
    T* _1 = factory();
    T* _2 = factory();
    return _1 == _2;
  }
};

#include "gtest/gtest.h"

//#include "helpers/iohelper.h"

//#include "exercise.cpp"


namespace
{
  class Evaluate : public testing::Test
  {
  };

  TEST_F(Evaluate, SimpleTest)
  {
    SingletonTester tester;
    ASSERT_TRUE(tester.is_singleton<SingletonTester>(
      [&]() -> SingletonTester* { return &tester; }))
      << "Expected a singleton in this case; provided lambda is yielding the same object over and over.";
    ASSERT_FALSE(tester.is_singleton<SingletonTester>([]() { return new SingletonTester{}; }));
  }
} // namespace


//int main(int ac, char* av[])
//{
//  testing::InitGoogleTest(&ac, av);
//  return RUN_ALL_TESTS();
//}