A simple snippet for button press filtering

button.c++

template<int pin>
class Button {
  bool state = false;
  int presses;
public:
  int poll() {
    int result = presses > 0;
    presses = 0;
    return result;
  }

  void update() {
    bool newState = !digitalRead(pin);
    // detect rising edge
    if (newState && !state) {
      presses += 1;
    }
    state = newState;
  }
};