c++ 精簡版 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();}