first-come-first-serve. This works!

fcfsv2.dart

void main() {
  // function call
  fcfs([
    // then this, secondly
    Task(
    't1', 10,
    ),
    // by rule, this should exec. first
    Task(
    't2', 0,
    ),
    // then this, lastly
    Task(
    't3', 15,
    ),
  ]);
}

class Task {
  String taskName;
  int arrivalTime;
  
  Task(this.taskName, this.arrivalTime);
  
  // doTask function
  void doTask(int taskId) {
    // TODO: find ways to automate this potentially long if-else statements
    if (taskId == 10) {
      print("I am task 1");
    } else if(taskId == 0) {
      print("I am task 2");
    } else {
      // task 3
      print("I am task 3");
    }
  }
}

void fcfs(List<Task> tasks) {
  // sort
  tasks.sort((a, b) => a.arrivalTime.compareTo(b.arrivalTime));
  
  // todo
  for(Task myTask in tasks) {
    // print(myTask.arrivalTime);
    print(myTask.taskName);
    
    // call myTask.doTask and pass arg
    int i = myTask.arrivalTime;
    myTask.doTask(i);
  }
}