yuan-kuan

void main() {
	final okNoError = {'ok': true, 'error':null};
	final errorNotOk = {'ok': false, 'error':true};
	final invalidMap = {'alien': 'invasion'};
  if (okNoError['ok'] ?? false) {
    print('ok, no error');
  }
  if (errorNotOk['ok'] ?? false) {
    print('will not print.');
  } else {

yuan-kuan

import 'package:dorker/dorker.dart';
import 'package:application/service.dart';

main() {
  Service(DorkerBoss());
}

yuan-kuan

Dorker _service;
if (const String.fromEnvironment('USE_WORKER') == 'true') {
  print('Asked to use worker');
  _service = DorkerWorker(Worker('worker/service.dart.js'));
} else {
  print('Not using worker');
  _service = Dorker();
  Service(Dorker.CrossLink(_service));
}

yuan-kuan

@JS()
library docker_web;

import 'dart:html' show Worker;

import 'package:js/js.dart';

import 'dorker_base.dart';

@anonymous

yuan-kuan

class Dorker<T> {
  @protected
  final incoming = StreamController<T>();
  @protected
  final outgoing = StreamController<T>();

  Stream<T> get onMessage => incoming.stream;
  Sink<T> get postMessage => outgoing.sink;
}

yuan-kuan

@JS()
library dogs;

import 'package:js/js.dart';

@JS()
@anonymous
class Dog {
  external String get name;
  external int get age;

yuan-kuan

import 'package:js/js.dart';

import 'package:excel_worker/dog.dart';

@anonymous
@JS()
abstract class MessageEvent {
  external dynamic get data;
}

yuan-kuan

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

import 'package:excel_worker/dog.dart';

void main() {
  var w = Worker('worker/dog_raiser.dart.js');

  // Listen to Worker's postMessage().
  // dart.html convert the callback to a Stream.