wait example without delay for esp8266/esp32 from Boris. Blame him if there are bugs

wait.ino

class Wait {
  public:
    Wait() : next_millis(0) {}
    bool operator()(unsigned long wait_millis, bool instant=false) {
      unsigned long current_millis = millis();
      if (next_millis == 0 && instant==false) next_millis = current_millis + wait_millis;
      if (current_millis >= next_millis) {
        next_millis = current_millis + wait_millis;
        return true;
      }
      return false;
    }
  protected:
    unsigned long next_millis;
};


void loop() {
      static Wait wait_1; // can be static or in protected or private section... 
      static Wait wait_2; // can be static or in protected or private section...
      if (wait_1(1000)) Serial.printf("Device \"%s\" is running...(%lu)\r\n", deviceId.toString().c_str(), millis() / 1000);
      if (wait_2(2000)) Serial.printf("Device \"%s\": this should run every 2nd second...\r\n", deviceId.toString().c_str());
}