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+---
+title: "CoffeeScript for Ruby Friends"
+date: 2010-08-06T00:00:00+00:00
+draft: false
+canonical_url: https://www.viget.com/articles/coffeescript-for-ruby-friends/
+---
+
+Hello there, Ruby friend. You've perhaps heard of
+[CoffeeScript](https://jashkenas.github.com/coffee-script/),
+"JavaScript's less ostentatious kid brother," but it might *as yet* be
+unclear why you'd want to stray from Ruby's loving embrace. Well,
+friend, I've been playing with it off-and-on for the past few months,
+and I've come to the following conclusion: **CoffeeScript combines the
+simplicity of Javascript with the elegance of Ruby.**
+
+## Syntax
+
+Despite its compactness as a language, Javascript has always felt a bit
+noisy to me. Its excessive punctuation is pretty much the only thing it
+has in common with its namesake. CoffeeScript borrows from the syntaxes
+of Ruby and Python to create a sort of minimalist Javascript. From
+Python, we get significant whitespace and list comprehensions.
+
+Otherwise, it's all Ruby: semicolons and parentheses around function
+arguments are entirely optional. Like Ruby's `||=`, conditional
+assignment is handled with `?=`. Conditionals can be inlined
+(`something if something_else`). And every statement has an implicit
+value, so `return` is unnecessary.
+
+## Functions
+
+Both Javascript and Ruby support functional programming. Ruby offers
+numerous language features to make functional programming as concise as
+possible, the drawback being the sheer number of ways to define a
+function: at least six, by my count (`def`, `do/end`, `{ }`, `lambda`,
+`Proc.new`, `proc`).
+
+At the other extreme, Javascript offers but one way to define a
+function: the `function` keyword. It's certainly simple, but especially
+in callback-oriented code, you wind up writing `function` one hell of a
+lot. CoffeeScript gives us the `->` operator, combining the brevity of
+Ruby with the simplicity of Javascript:
+
+```coffeescript
+thrice: (f) ->
+  f()
+  f()
+  f()
+
+thrice -> puts "OHAI"
+```
+
+Which translates to:
+
+```javascript
+(function(){
+  var thrice;
+
+  thrice = function(f) {
+    f();
+    f();
+    return f();
+  };
+
+  thrice(function() { return puts("OHAI"); });
+})();
+```
+
+I'll tell you what that is: MONEY. Money in the BANK.
+
+## It's Node
+
+Though not dependent upon it, CoffeeScript is built to run on top of
+[Node.js](http://nodejs.org/). This means you can take advantage of all
+the incredible work people are doing with Node, including the
+[Express](http://expressjs.com/) web framework, the [Redis Node
+Client](https://github.com/fictorial/redis-node-client), and
+[Connect](https://github.com/senchalabs/connect), a middleware framework
+along the lines of [Rack](http://rack.rubyforge.org/). What's more, its
+integration with Node allows you to run CoffeeScript programs from the
+command line just like you would Ruby code.
+
+CoffeeScript is an exciting technology, as both a standalone language
+and as a piece of a larger Node.js toolkit. Take a look at
+[Defer](http://gfxmonk.net/2010/07/04/defer-taming-asynchronous-javascript-with-coffeescript.html)
+to see what the language might soon be capable of, and if you're
+participating in this year's [Node.js
+Knockout](http://nodeknockout.com/), watch out for the
+[Rocketpants](http://nodeknockout.com/teams/2eb41a4c31f50c044a280000).