Simple event system in C++

event.cpp

#include <functional>
#include <map>
#include <typeinfo>
#include <iostream>

struct Event {
	virtual ~Event() {}
};
struct TestEvent : Event {
	std::string msg;
	TestEvent(std::string msg) : msg(msg) {}
};


// Has the limitation that on<T> will not catch subtypes of T, only T.
// That may or may not be a problem for your usecase.
//
// It also doesn't (yet) let you use the subtype as an argument.

typedef std::multimap<const std::type_info*,
					  const std::function<void(const Event&)>> EventMap;

class event {
	private:
		static EventMap eventMap;

	public:
		template<typename EventWanted>
		static void on(const std::function<void(const Event&)>& fn) {
			event::eventMap.emplace(&typeid(EventWanted), fn);
		}

		static void emit(const Event& event) {
			auto range = eventMap.equal_range(&typeid(event));
			for(auto it = range.first; it != range.second; ++it)
				it->second(event);

		}
};

EventMap event::eventMap;

int main() {
	// bind some event handlers
	event::on<TestEvent>([](const Event& e) { std::cout << "hi from " << static_cast<const TestEvent&>(e).msg << std::endl; });
	event::on<TestEvent>([](const Event& e) { std::cout << "hi two" << std::endl; });
	
	// fire some events
	event::emit(TestEvent("pinkie"));
	event::emit(TestEvent("the brain"));
}