!7

static JTextField tf;
static JTextArea textArea;

sclass ConcurrentEvaluator {
  new L functions;
  L results = synchroList();
  ExecutorService executorService;
  O onNewResult; // Runnable or voidfunc(int)
  
  void add(O f) { functions.add(f); }
  
  void start() {
    executorService = Executors.newFixedThreadPool(numberOfCoresToUse());
    while (l(results) < l(functions)) results.add(null);
    for _i over functions: {
      final int i = _i;
      executorService.execute(r {
        results.set(i, pcallF(functions.get(i)));
        onNewResult(i);
      });
    }
  }
  
  void onNewResult(int i) { pcallF(onNewResult, i); }
  
  L results() { ret cloneList(results); }
}

p-substance {
  showFrame(northAndCenter(tf = jtextfield(), textArea = jtextarea()));
  final ReliableSingleThread thread = new(f update);
  onEnter(tf, r { thread.trigger() });
}

svoid update {
  final new ConcurrentEvaluator eval;
  eval.add(func { ret "Hello at " + now(); });
  eval.add(func { sleepSeconds(1); ret "Hello 2 at " + now(); });
  eval.onNewResult = r { updateResults(eval) };
  eval.start();
}

svoid updateResults(ConcurrentEvaluator eval) {
  L l = notNullOnly(eval.results());
  S text = lines(allToString(l));
  setText(textArea, text);
}