#ifndef OBSERVER_HH

#define OBSERVER_HH

namespace openmsx {

/**

 * Generic Gang-of-Four Observer class, templatized edition.

 */

template<typename T> class Observer

{

public:

	Observer(const Observer&) = delete;

	Observer(Observer&&) = delete;

	Observer& operator=(const Observer&) = delete;

	Observer& operator=(Observer&&) = delete;

	virtual void update(const T& subject) noexcept = 0;

	virtual void subjectDeleted(const T& /*subject*/) { /*nothing*/ }

protected:

	Observer() = default;

	~Observer() = default;

};

} // namespace openmsx

#endif