Dart: The Dawn of Web Apps

Transcript

1. Come to the Dart side! We have cookies!
2. Dart: The Dawn of Web Apps ladicek.github.com
3. 500 000 lines of JS
4. 500 000 lines of JS Say hello to Dart!
5. main() { print("Hello, Dart!"); }
6. class Person { var name, age; Person(this.name, this.age); toString() => "$name ($age years)"; } main() { var me = new Person("Ladislav Thon", 30); print(me); }
7. Optional typing void main() { Person me = new Person("Ladislav Thon", 30); List<Person> people = [me, ...]; people.forEach((Person person) => print(person)); people.forEach((person) { // iterable print(person); }); people.forEach(print); // closurization }
8. Innocent until proven guilty
9. Client-side code import 'dart:html'; main() { query('#button').onClick.listen((event) { // stream ... }); }
10. Server-side code import 'dart:io'; main() { HttpServer.bind('127.0.0.1', 1337).then((server) { // future server.listen((request) { // stream … }); }); }
11. Isolates import 'dart:isolate'; main() { var box = new MessageBox(); streamSpawnFunction(worker).add( { 'replyTo': box.sink, 'value': ... } ); // sink box.stream.listen((response) { ... }); // stream } worker() { stream.listen((message) { ... }); }
12. Mirrors import 'dart:mirrors'; main() { var person = new Person(...); var personMirror = reflect(person); personMirror.getField('name').then((resultMirror) { print(resultMirror.reflectee); }); // async today, probably sync in the future }
13. And a lot more
14. Implicit interfaces & properties abstract class Person { get name; get age; set age(value); } class Monster implements Person { final name = 'Cthulhu'; var age = '?!?!?!'; }
15. Inheritance & mixins class Entity { int id; } // or whatever abstract class Named { get name; toString() => '$name'; } class Person extends Entity with Named { get name => 'Cthulhu'; }
16. Optional parameters class Person { var name, age; Person({this.name: '<unknown>', this.age: 0}); growOlder([years = 1]) { age += years; } } main() { var me = new Person(name: 'Ladislav Thon'); me.growOlder(30); }
17. Constructors class Person { final name, age; Person(this.name, this.age); Person.me() : name = 'Ladislav Thon', age = 30; static Person cache; factory Person.cachedMe() { if (cache == null) { cache = new Person.me(); } return cache; } }
18. Cascades class Person { var name, age; } main() { var me = new Person() ..name = 'Ladislav Thon' ..age = 30; }
19. Privacy class Person { var _isEnemy; var name, age; } main() { // in another library var me = ...; print(me._isEnemy); // NO! }
20. class Proxy { var target; Proxy(this.target); noSuchMethod(invocation) { print('Calling ${invocation.memberName}'); return invocation.invokeOn(target); } }
21. Web UI
22. Web UI Web Components
23. Web UI MDV Templates
24. Web UI Polyfill for current browsers
25. HTML part <element name="x-counter" constructor="Counter" extends="div"> <template> <span>{{value}}</span> <button on-click="increment()">+1</button> </template> <script type="application/dart">...</script> </element>
26. Dart part import 'package:web_ui/web_ui.dart'; class Counter extends WebComponent { int value = 0; increment() { value++; } }
27. Usage <html> <head> <link rel="components" href="counter.html"> </head> <body> <x-counter></x-counter> <script type="application/dart">main() {}</script> </body> </html>
28. Conditions & iteration <table template if="rows != null && !rows.isEmpty"> <tr template iterate="headerItem in header"> <th>{{headerItem}}</th> </tr> <tbody template iterate="row in rows"> <tr template iterate="item in row"> <td>{{item}}</td> </tr> </tbody> </table>
29. Passing values <html> <head> <link rel="components" href="grid.html"> </head> <body> <x-grid header="{{header}}" rows="{{rows}}"> </x-grid> <script type="application/dart">...</script> </body> </html>
30. Performance Fast startup
31. Performance Fast runtime (beats V8 already)
32. Tooling Eclipse, IntelliJ IDEA vim, Sublime Text
33. So what is it all about?
34. So what is it all about? Structure!
35. www.dartlang.org
36. ladicek.github.com ?