gistfile1.cpp

class Speaker
{
	public:
		struct Scope
		{
			Scope(bool verbose = false) { resetCounters(); setVerbose(verbose); }
			~Scope() { printStats(); }
		};

		~Speaker() { speak() << "destructor" << std::endl; ++_counters.dtor; }

		Speaker(): _id(getNextId())
		{ speak() << "constructor" << std::endl; ++_counters.ctor; }
		
		Speaker(const Speaker& from): _id(getNextId())
		{ speak() << "copy constructor from " << from.getName() << std::endl; ++_counters.cctor; }

		Speaker& operator=(const Speaker& from)
		{ speak() << "affectation from " << from.getName() << std::endl; ++_counters.aff; return *this; }

		Speaker(Speaker&& from): _id(getNextId())
		{ speak() << "move constructor from " << from.getName() << std::endl; ++_counters.mcctor; }

		Speaker& operator=(Speaker&& from)
		{
			speak() << "move affectation from " << from.getName() << std::endl;
			++_counters.maff;
			return *this;
		}

		std::ostream& speak(std::ostream& os = std::cout) const
		{
			if (_counters.verbose)
			{
				os << getName() << ": ";
				return std::cout;
			}
			static struct PlaceHolder: public std::ostream { } placeHolder;
			return placeHolder;
		}

		friend std::ostream& operator<<(std::ostream& os, const Speaker& spkr)
		{
			std::ostream::sentry init(os);
			if (init)
				os << spkr.getName();
			return os;
		}

		static void resetCounters()
		{
			bool verbose = _counters.verbose;
			_counters = SpeakerCounters();
			_counters.verbose = verbose;
		}

		static void setVerbose(bool verbose = true) { _counters.verbose = verbose; }

		static std::ostream& printStats(std::ostream& os = std::cout)
		{
			os << "SpeakerCnters"
				<< " dtor=" << _counters.dtor
				<< " ctor=" << _counters.ctor
				<< " cctor=" << _counters.cctor
				<< " mcctor=" << _counters.mcctor
				<< " aff=" << _counters.aff
				<< " maff=" << _counters.maff
				<< std::endl;
			return os;
		}

	private:
		static struct SpeakerCounters
		{
			unsigned nextId; // uniq id
			unsigned dtor;   // destructor
			unsigned ctor;   // constructor
			unsigned cctor;  // copy constructor
			unsigned mcctor; // move constructor
			unsigned aff;    // affection
			unsigned maff;   // move affection
			bool     verbose;

			SpeakerCounters():
				nextId(0),
				dtor(0),
				ctor(0),
				cctor(0),
				mcctor(0),
				aff(0),
				maff(0),
				verbose(false)
			{}
		} _counters;

		unsigned _id;

		unsigned getNextId() const { return _counters.nextId++; }

		std::string getName() const
		{
			std::ostringstream os;
			os << "Speaker" << _id;
			return os.str();
		}
};
Speaker::SpeakerCounters Speaker::_counters;