klips/cpp/patterns/singleton/singleton-pointer.hpp

36 lines
1.0 KiB
C++
Raw Normal View History

2021-05-11 16:21:03 +00:00
#ifndef SINGLETON_POINTER_HPP
#define SINGLETON_POINTER_HPP
#include <iostream>
#include <string>
class ClassicSingleton{
public:
// returns pointer to single getInstance
static ClassicSingleton* getInstance();
// example functions manipulating singleton object
inline void showMessage() const { std::cout << message;}
void updateMessage(const std::string &m) { message=m;}
private:
// Do not allow construction of this object; Use getInstance() instead
ClassicSingleton(){ message = "New ClassicSingleton\n";}
// Do not allow copying of this object
ClassicSingleton(const ClassicSingleton&){}
// Ignore -Wreturn-type warnings; It's intentional for this pattern
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wreturn-type"
2021-05-11 16:21:03 +00:00
ClassicSingleton& operator=(const ClassicSingleton&){}
// Unmatched pop reverts GCC to commandline options
#pragma GCC diagnostic pop
#pragma GCC diagnostic pop
2021-05-11 16:21:03 +00:00
// Static pointer to instance of this singleton
static ClassicSingleton* instance;
std::string message;
};
#endif // SINGLETON_POINTER_HPP