c++ 精简版 signal

#pragma once

#include <functional>

#include <map>

using namespace std;



template<typename x>

struct signal;



template <typename ret_t, typename... args_t>

struct signal<ret_t(args_t...)> {

	typedef int key_t; //

	typedef function<ret_t(args_t...)> func_t;



	key_t nextkey_t;

	map<key_t, func_t> connections;



	key_t operator+=(func_t f) {

		key_t k = nextkey_t++;

		connections[k] = f;

		return k;

	}



	void operator-=(key_t k){

		connections.erase(k);

	}



	void operator()(const args_t&... args) {

		for(auto conn : connections) {

			(conn.second)(args...);

		}

	}

};

test:

 

int main() {

	

	signal<void()> sig;

	int k = sig += [](){ cout << "111" << endl; };

	sig += [](){ cout << "222" << endl; };



	sig -= k;

	sig();

}