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From Rosetta Code
This programming language may be used to instruct a computer to perform a task.
Official website
See Also:

Listed below are all of the tasks on Rosetta Code which have been solved using CoffeeScript.
Your Help Needed
If you know CoffeeScript, please write code for some of the tasks not implemented in CoffeeScript.
This page uses content from Wikipedia. The original article was at CoffeeScript. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
CoffeeScript is a programming language that compiles to JavaScript. The language adds syntactic sugar inspired by Ruby and Python to enhance JavaScript's brevity and readability, as well as adding more sophisticated features like array comprehension and pattern matching.

With 4000+ watchers and 300+ forks (as of December 2011), CoffeeScript is ranked as one of the "most interesting" projects on Github. [1] The language has a relatively large following in the Ruby community, and has been used in production by 37signals. Ruby on Rails began to include CoffeeScript in its asset pipeline in Rails version 3.1 (see [2]).


On December 13, 2009, Jeremy Ashkenas made the first git commit of CoffeeScript with the comment: "Initial commit of the mystery language." The compiler was written in Ruby. On December 24th, he made the first tagged and documented release, 0.1.0. On February 21, 2010, he committed version 0.5, which replaced the Ruby compiler with one written in pure CoffeeScript. By that time the project had attracted several other contributors on Github, and was receiving over 300 page hits per day.

On December 24, 2010, Ashkenas announced the release of stable 1.0.0.


A common JavaScript snippet using the jQuery library is

$(document).ready(function() {
// Initialization code goes here

or even shorter,

$(function() {
// Initialization code goes here

In CoffeeScript, the function keyword is replaced by the -> symbol, and indentation is used instead of curly braces (except when defining an associative array), as in Python. Also, parentheses can usually be omitted. Thus, the CoffeeScript equivalent of the snippet above is

$(document).ready ->
# Initialization code goes here


$ ->
# Initialization code goes here


The CoffeeScript compiler has been written in CoffeeScript since version 0.5, and can be run either in the browser or through Node.js. The official site at has a "Try CoffeeScript" button in the menu bar; clicking it opens a modal window in which you can enter CoffeeScript, see the JavaScript output, and run it directly in the browser.


  1. Github. "Interesting Repositories", Github, Nov 10, 2010.
  2. Carson, Ryan. "New Rails-like Framework from 37signals for HTML5 Mobile Apps", Think Vitamin blog, Nov 8, 2010.
  3. Hagenburger, Nico. "Rails 3.1 – A Sneak Preview", presentation for Railscamp Hamburg on Oct 23, 2010.
  4. Ashkenas, Jeremy. "The Plan for 1.0", Github issue tracker, Nov 4, 2010.

External links[edit]


This category has the following 3 subcategories, out of 3 total.

Pages in category "CoffeeScript"

The following 211 pages are in this category, out of 211 total.