Coffeescript

CoffeeScript
Like JavaScript, but without the horrible.

Sunday, 27 November, 11

Burke Libbey
Me @burkelibbey


The 5 Second Pitch


var foo = function() {
JavaScript return "bar";
}

CoffeeScript foo = -> "bar"


“Sold! What did I just buy?”


“CoffeeScript is a little language
that compiles into JavaScript”
– Jeremy Ashkenas, CoffeeScript author


foo = -> "bar"

CoffeeScript Compiler

(function() {
var foo;
foo = function() {
return "bar";
};
}).call(this);


“What’s wrong with JavaScript?”

Browser inconsistencies

Terrible DOM API

Redundant syntax




Terrible DOM API

Redundant syntax

Most of the issues people have with JavaScript
boil down to these three points.




Terrible DOM API

Redundant syntax

jQuery does a fantastic job of shielding you
from these two.




Terrible DOM API

Redundant syntax

CoffeeScript fixes this one.


So what’s wrong with the syntax?

function(x) {
return x * x;
}

For a functional language, having to write “function”
and “return” everywhere is more than a little strange.


Anonymous Function Syntax

JavaScript function(x) { return x * x; }

Scheme (lambda (x) (* x x))

Erlang fun(X) -> X * X end.

CoffeeScript (x) -> x * x

Haskell x -> x * x

Clojure #(* % %)


“I’m a masochist, and I like
typing a lot. Give me another
reason.”


Rails 3.1 includes CoffeeScript
by default.


...to the chagrin of hypocrites the
world over.


Fighting Rails is usually doomed
to failure.


So just suck it up and learn
CoffeeScript.


Without further ado:
CoffeeScript Whirlwind tour


three = -> 3

square = (x) -> x * x

add = (x, y)
x + y


Default values!
fill = (container, liquid = "coffee") ->
"Filling the #{container} with #{liquid}..."

...and string interpolation!


YAML-like hash literals work
kids =
brother:
name: "Max"
age: 11
sister:
name: "Ida"
age: 9


Never type “var” again!
CoffeeScript does it for you.


mood = greatlyImproved if singing


if happy and knowsIt
clapsHands()
chaChaCha()
else
showIt()


date = if friday then sue else jill


options or= defaults


I’m out of slides. Time for
live-coding!


Thanks!


Coffeescript

Recommended

Recommended

More Related Content

More from Burke Libbey

More from Burke Libbey (7)

Recently uploaded

Recently uploaded (20)

Coffeescript