#include <string>
#include <iostream>
#include <vector>

class Object
{
public:
  Object(const std::string & content) : m_content(content) {}
    
  const std::string & getContentByConstRef() const
  {
    return m_content;
  }
    
  void setContent(const std::string & content)
  {
    m_content = content;
  }

private:
  std::string m_content;
};

void possiblyUnexpectedBehaviour()
{
  Object test("Some string.");

  const std::string & message = test.getContentByConstRef();
    
  std::cout << message << std::endl;
    
  // The message variable is changing under our feet.  In real code, this may
  // be obfuscated and not very easy to debug.
  test.setContent("Some other string you may not be expecting.");
    
  std::cout << message << std::endl;
}

const std::string & getString()
{
  Object test("This is a string.");
    
  // Uh-oh, we're passing a reference to something that is about to disappear!
  return test.getContentByConstRef();
}

void undefinedBehaviour()
{
  std::cout << "Bad ===> " << getString() << " <=== Bad" << std::endl;
}

int main() 
{
  possiblyUnexpectedBehaviour();
    
  undefinedBehaviour();
}