Publish subscribe

test.cpp

#include <iostream>
using namespace std;

class Broker {

  public:
  Broker() : pos(0) {}

  void subscribe(void (*f)()) {
    _f[pos] = f;
    pos++;
  }

  void notify() {
    for (int i = 0; i < pos; i++) {
      (_f[i])();
    }
  }

  private:
  void (*_f[10])();
  int pos;
};

void m2() {
  cout << "m2";
}

int main() {
  Broker b;
  b.subscribe(&m2);
  b.subscribe(&m2);
  b.notify();
}