example1.dart

import 'dart:async';
import 'dart:html' as html;

stream() {
  final sc = new StreamController();

  spawn(ms, id) =>
    new Timer.periodic(new Duration(milliseconds: ms), (_) => sc.add(id));

  spawn(250, 1);
  spawn(1000, 2);
  spawn(1500, 3);

  return sc.stream;
}

void main() {
  html.document.body.appendHtml('<div id="out" />');
  final q = [];
  stream().listen((msg) {
    q.add(msg);
    if (q.length > 10) q.removeAt(0);

    html.query("#out").innerHtml = q.map((id) => "<div class='proc-${id}'>Process ${id}</div>").join('');
  });
}

example3.dart

import 'dart:html' as html;

void main() {
  html.document.body.appendHtml('<div id="out" style="width: 100px; height: 100px;"/>');

  offset(em) =>
    (e) => e.client - em.client.topLeft;

  final out = html.query("#out");
  out.onMouseMove.map(offset(out)).listen((p) { 
    out.innerHtml = "(${p.x}, ${p.y})";
  });
}

example5.dart

import 'dart:async';
import 'dart:math' as math;

final random = new math.Random();
randomDuration(max) => new Duration(milliseconds: random.nextInt(max));

fakeSearch(kind) =>
  (sc, query) =>
    new Timer(randomDuration(100), () { sc.add([kind, query]); });

final web1 = fakeSearch("web1");
final web2 = fakeSearch("web2");
final image1 = fakeSearch("image1");
final image2 = fakeSearch("image2");
final video1 = fakeSearch("video1");
final video2 = fakeSearch("video2");

fastest(query, servers) {
  final sc = new StreamController();

  for (var server in servers)
    server(sc, query);

  return sc.stream.take(1);
}

class Timeout { }

Future<List> search(query) {
  final sc = new StreamController();

  fastest(query, [web1, web2]).listen(sc.add);
  fastest(query, [image1, image2]).listen(sc.add);
  fastest(query, [video1, video2]).listen(sc.add);

  new Timer(const Duration(milliseconds: 50), () => sc.add(new Timeout()));

  return sc.stream.takeWhile((m) => m is !Timeout).take(3).toList();
}

void main() {
  search("Dart").then(print);
}