A brief introduction to Dart

1. Tópicos em Tecnologia da Computação
Lucas Leal

2. Agenda
• What is Dart?
• Why did Google create Dart?
• Does the web really need another language?
• What is NEW about Dart?
• Why does Dart look so familiar?
• How can I play with Dart? Is there a real
editor?

3. Agenda
• What is in the platform? **
• Should I use Dart for my application today?
• Who is using Dart in production?
• Learn more…

5. What is Dart?
• Open-source web programming language
developed by Google.
• First appearing in GOTO conference in Aarhus,
Denmark, October 10-12, 2011.
• Class-based, single-inheritance, object
oriented language with C-style syntax.
• It supports interfaces, abstract classes, reified
generics, and optional typing.

6. What is Dart?
• “Batteries included.”
– Language and libraries
– Tools
– VM
– Compiler to JavaScript

7. Why did Google create Dart?
• “We want you to be able to create great web
apps. Great web apps improve the web, and
when the web does better, everyone wins.”
(Walrath, K; Ladd, S)

8. Why did Google create Dart?
• “Dart helps developers from all platforms
build complex, high performance client apps,
for the future web,” (Ladd, S)
– All platforms: iOS, Android, Java, .NET, C#, C++…
– More features, functionalities, integrated
– Zero latency, fast computational execution

9. Why did Google create Dart?
• In another words…
• “Runs web applications at least 2 times faster
as it’s possible with JS in V8”
• JavaScript makes the work hard when the
application

10. Does the web really need another
language?
• Yes, it does!
• Pros:
– Developing small applications is easy
– Platform independence
– Non installation of applications
– Supports incremental development
– It is EVERYWHERE…

11. Does the web really need another
language?
• Cons:
– Developing large-scale applications is hard
– No support for libraries
– Startup performance is bad
• That said, Dart comes to fill those gaps
– No competition with JavaScript (kind of…)

12. What is NEW about Dart?
• Dart uses a different type checker - “Innocent
until proven guilty”
• Nice and compact way to implement a
function that evaluates and return a single
expression
• Snapshots
• Generics, but easy!
• HTML library, reusability…

13. Why does Dart look so familiar?
• They want more than 5 users…
• Designed for mass adoption
• Scripting language users (JavaScripters), and
structured language users (Java developers)
• Anyone familiar with Java, or a C language
should be able to quickly understand Dart

14. Why does Dart look so familiar?
class Point {
Point(this.x, this.y);
distanceTo(other) {
var dx = x - other.x;
var dy = y - other.y;
return Math.sqrt(dx * dx + dy * dy);
}
var x, y;
}
main() {
var p = new Point(2, 3);
var q = new Point(3, 4);
print(‘distance from p to q = ${p.distanceTo(q)}’);
}

15. How can I play with Dart? Is there a
real editor?
• DartPad
– Executes Dart code interactive in any modern
browser
– dartpad.dartlang.org
– Provides some code examples

16. How can I play with Dart? Is there a
real editor?

17. How can I play with Dart? Is there a
real editor?

18. How can I play with Dart? Is there a
real editor?

19. How can I play with Dart? Is there a
real editor?

20. How can I play with Dart? Is there a
real editor?
• Dart Editor
– Available for Windows, Mac, and Linux
– It’s made simple: just select a file and click ‘Run’
– Dart Editor compile your Dart code to JavaScript
– Features and tools that helps editing Dart code

21. How can I play with Dart? Is there a
real editor?
• ]

22. How can I play with Dart? Is there a
real editor?
• Dartium

23. How can I play with Dart? Is there a
real editor?
• Dartium

24. How can I play with Dart? Is there a
real editor?
• It’s integrated with Chromium (also
nicknamed Dartium)
• Dart SDK

25. What is in the platform?
• Language specifications
• Libraries
• Compiler to JavaScript
• VM
• Integration with Chromium
• Dart Editor

26. Should I use Dart for my application
today?
• The definitely is YES!
• There are a lot of companies using Dart in
production
• The benefits are relevant as showed

27. Should I use Dart for my application
today?

28. Should I use Dart for my application
today?

29. Should I use Dart for my application
today?

30. Should I use Dart for my application
today?

31. Benchmarking
• DeltaBlue is a one-way constraint solver, originally
written in Smalltalk by John Maloney and Mario
Wolczko. The main focus in DeltaBlue is on
polymorphism and object-oriented programming.
• FluidMotion is a 2D Navier-Stokes equations solver,
originally written in JavaScript by Oliver Hunt. The main
focus is on accessing numeric arrays, as well as doing
floating-point arithmetic.
• Havlak algorithm is an extension of Tarjan’s interval-
finding algorithm that deals with irreducible graphs,
and constructs a loop-nesting forest for an arbitrary
flow graph

32. Benchmarking
• Richards is an OS kernel simulation benchmark, originally written in
BCPL by Martin Richards. The main focus in Richards is on property
access and calling functions and methodspolymorphism and object-
oriented programming.
• Tracer is a ray tracer benchmark, originally written in JavaScript by
Adam Burmister. Both Adam’s and the Octane version in JavaScript
use the class emulation pattern from the prototype.js library.
Because Dart has a native class system, it’s unfair to do a direct
performance comparison with the Octane version. We therefore
compare Dart performance with an improved JavaScript version
called Tracer. The improved version uses only constructors and
prototypes without any abstraction layers in between; it runs 50%
faster than the original Raytrace JavaScript benchmark in Octane.

38. Who is using Dart in production?
• A bunch of companies listed on Dart’s website
https://www.dartlang.org/community/who-
uses-dart.html
• Google Fiber

39. Learn more…
• The main place to go for Dart information is
dartlang.org
• Official news: Dart News & Updates
• Dartosphere (single feed of many Dart blogs)
• Good interviews and videos about Dart:
– InfoWorld interview with Lars Bak (15 Nov 2011)
– Dartisans hangout with Seth Ladd, Vijay Menon, and
Anton Muhin (15 Feb 2012)
– Transcription of Gilad Bracha’s quick tour of Dart (2
Nov 2011)

40. References
• Dart’s website: https://www.dartlang.org.
• Walrath, K; Ladd, S. What is Dart? O’Reilly, March 2012,
CA, EUA.
• Walrath, K. What is Dart? Available on:
http://radar.oreilly.com/2012/03/what-is-dart.html.
O’Reilly, March 21, 2012. Accessed on May 27, 2015.
• InfoWorld interview: Why Google Dart beats JavaScript,
by Paul Krill. Available on:
http://www.javaworld.com/article/2078464/mobile-
java/infoworld-interview--why-google-dart-beats-
javascript.html.

41. References
• IODev Blog. Dart… Dart… Dart… What is Dart?. June
11, 2012. Available on: http://iodev-
blog.blogspot.com.br/2012/06/dartdartdartwhat-is-
dart.html.
• Seth Ladd’s Blog. Available on:
http://blog.sethladd.com.