main.dart

import 'dart:async';

// This is a workaround because sleep from dart:io breaks DartPad instead we're using a Future
Future sleep1() {
  return new Future.delayed(const Duration(seconds: 1), () => "1");
}

void main() {

  do_long_running_fancy_stuff() {
    print("FANCY STUFF DONE1");
    sleep1();
    print("FANCY STUFF DONE2");
    sleep1();
    print("NOW IM DONE");
  }

  Future foobar()  {
  	return new Future(() {
    	do_long_running_fancy_stuff();
  	});
	}
  
  foobar();
  
  print("I'M DONE ... but wait ...");
}