Google Dart vs CoffeeScript? Which one should one learn?

Question

I was thinking about learning CoffeeScript some time in the future. In the mean time, Google came out with Dart that seems to do what CoffeeScript does.

Google says:

Dart code can be executed in two different ways: either on a native virtual machine or on top of a JavaScript engine by using a compiler that translates Dart code to JavaScript. This means you can write a web application in Dart and have it compiled and run on any modern browser.

Does anyone know advantages and disadvantages of learning Dart or CoffeeScript?

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Update on the status of Dart, Feb 28, 2012

Google is planning to integrate Dart into Chrome browser. As of now, Dart programs can run directly on the Dart VM in Chromium.

Answer 1

Learn Javascript, use CoffeeScript, check out Dart.

Learn Javascript

• The best way to learn (and debug) Coffeescript
• Dart is similar enough to JS but far less common. You will come across more JS than Dart.
• To understand why CoffeeScript exists, and how Dart differs.

Use Coffeescript

• CoffeeScript is out there in projects already, so there's community and experience.
• CoffeeScript might come up at work sooner than Dart (esp. with Rails).
• CoffeeScript is nice!

Check out Dart

If you understand Javascript, and use CoffeeScript, and have checked out Dart, you'll be in a good position to judge which hammer is best for the task. Most JS/CS knowledge should be transferrable to Dart, the other way around would be more difficult.

I love opinion pieces :D

Answer 2

This is subjective question... but...

Personally, I like how succinct CoffeeScript is. Dart looks more like Java to me, which makes it less appealing. I am fond of the significant shortcuts that CoffeeScript provides such as lambda notation, optional curly braces and key/value notations.

Honestly, though, I think CoffeeScript and Dart are just steps in a much bigger movement... to bring any language to the browser. We already have compilers that will take pretty much any language to JavaScript but the development story is still pretty crappy without browser support of some kind.

CoffeeScript and Dart will push the browsers to support debugging of other languages and build an ecosystem around other languages. Once that is solidified, I think we will move away from CoffeeScript/Dart and move towards our language of choice.

So, for the time being, find the language that suits you best and go forward with it. For me, it is CoffeeScript.

Answer 3

CoffeeScript still is Javascript with prototype based objects, its intend is to extend and improve upon Javascript.

Dart is not Javascript. It's a completely new language which only relates to Javascript in that it has compiler to Javascript. Googles long-term goal with Dart is to make all browsers include a new script-engine that directly runs Dart, the crosscompiler to Javascript just is a placeholder for the real thing till that happens.

Choosing one over the other is making a bet on whether or not Google will succeed with Dart. As an alternative to CoffeeScript Dart can only be inferior because it doesn't support the Javascript object model.

Answer 4

I'd vote for Coffeescript because it is already popular, has a simple syntax, and is the good parts of Javascript. Dart is unproven and may never see wide adoption.

(Even if it turns out that Dart overtakes Javascript, they'll probably just have Coffeescript compile to Dart instead) :)

Answer 5

It's worth noting that Coffeescript is not a "whole new language" as someone said above. Coffeescript can be seen as an alternative syntax for javascript. Under the hood, it's just javascript, with the same data types and object model. Coffeescript was created to provide a more succinct, expressive and powerful syntax while fixing its bad parts.

Having been implementd as a trans-compiler (or transpiler, which is a source to source compiler) I believe Coffeescript is the safer bet in the long term.

Creating a transpiler is easier than creating a whole language interpreter or vm from scratch, because you are leveraging an existing target. So, if Dart turns out to be a good target, chances are that someone will come up with a Coffee-to-Dart transpiler soon (or something that comes close).

You should decide which syntax you find more of your liking: C-like syntax (such as Java's or javascript's) or Pythonic-Rubyist syntax (more modern, expressive and, IMHO, more beautiful).

Answer 6

Do you already know Javascript? If not, learn it first, then learning coffeescript will be a small step.

Dart has just been announced, at the moment it's just a curiosity. Take another look at it in a year :)

Answer 7

When this company says that it will replace JS in the future, i think that's going to happen

This company - Google - develops, then drops, new technologies, all the time. How many people are using Google's "GO" language? Then there is Buzz, Wave, and many other projects that have been dropped by Google.

Answer 8

When this company says that it will replace JS in the future, i think that's going to happen, it's the first time that a new language is not only introduced but thought of being able to achieve such a target. In addition, the company is powerful enough to be able to change the way the web moves, so yes that's what it's probably going to be.