CoffeeScript

CoffeeScript - Intro

@d_danailov

CoffeeScript : Intro

Dimitar DanailovSenior Developer at 158ltd.com

dimityr.danailov[at]gmail.comGithub

Founder at VarnaITSenior Developer at 158ltd.com

Cleaner Code With CoffeeScriptGithub Code

Topics Today

● Introduction● Installing CoffeeScript● Using CoffeeScript Files● Learning the Core Functionality● Data Types● Comments and Functions● Operators

Topics Today (2)

● Control Structures● Loops and Comprehensions● Scope and Context● Stirring in Advanced Concepts● Object Prototypes● CoffeeScript Classes● Heregexes● Using CoffeeScript in the Browser

Installing CoffeeScript

1. Node.js2. NPMsudo apt-get install nodejs npm &&

3. sudo npm install -g coffee-script4. coffee -v

Using CoffeeScript Files

node.js file.jscoffee file.coffeecoffee -c file.coffeecoffee -cw file.coffeecoffee (read–eval–print loop (REPL))

Variables

Booleans :● true/false● yes/no● on/off

Variables (2)

Destructuring Assignment :

theBait = 1000

theSwitch = 0

[theBait, theSwitch ] = [theSwitch, theBait]

Variables (3)

Destructuring Assignment :weatherReport = (location) ->

# Make an Ajax request to fetch the weather...

[location, 72, "Mostly Sunny"]

[city, temp, forecast ] = weatherReport "Berkeley, CA"

Comments

# Single line comment

###

Multi line comment

###

Functions

Splats :

The JavaScript arguments object is a useful way to work with functions that

accept variable numbers of arguments. CoffeeScript provides splats ..., both

for function definition as well as invocation, making variable numbers of

arguments a little bit more palatable.

# Splats:

race = (winner, runners...) ->

print winner, runners

Operators● JS : == / Coffee : is ● JS : != / Coffee : isnt● JS : if (!false) / Coffee : if not false ● JS : && / Coffee : AND● JS : || / Coffee : OR

Condition statements

● if● if not● unless● switch and when

Loops and Comprehensions

Most of the loops you'll write in CoffeeScript will be comprehensions over arrays, objects, and ranges. Comprehensions replace (and compile into) for loops, with optional guard clauses and the value of the current array index. Unlike for loops, array comprehensions are expressions, and can be returned and assigned.

Loops

● for● while● until ● loop used with break !!!

Scope

● coffee -c --bare file.coffee● this● root = (export ? window)

Prototype

Classes

Regular Expressions

Similar to block strings and comments, CoffeeScript supports block regexes — extended regular expressions that ignore internal whitespace and can contain comments and interpolation. Modeled after Perl's /x modifier, CoffeeScript's block regexes are delimited by /// and go a long way towards making complex regular expressions readable.

Using CoffeeScript in the Browser

● coffee -c --watch *.coffee● coffee -c --watch o js src/*.coffee● http://coffeescript.org/#scripts

Questions ?

Dimitar DanailovSenior Developer at 158ltd.com

dimityr.danailov[at]gmail.comGithub

Founder at VarnaITSenior Developer at 158ltd.com

Cleaner Code With CoffeeScriptGithub Code