Have a cup of coffee

From an outside look of it, I think it’s like a mixture of Python and Ruby. —Nango 

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greet = (message) ->
  alert message

Advantages

  • Least amount of code to solve problems
  • Readable and Understandable
  • Easy to Maintain
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message = "Ready for some Coffee?"
alert(message)

=>

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var message;
message = "Ready for some Coffee?";
alert(message);

All the code is wrapped up in a closure to prevent variable pollution

Use a default value of ‘Stranger’ for the name parameter

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greet = (name='Stranger') -> alert name

=>

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var greet;
greet = function(name) {
  if (name == null) {
    name = 'Stranger';
  }
  return "Hello, " + name;
};

Kind of Like Ruby ha, But In this field, it is called CoffeeScript-style string interpolation.

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greet = (name='Stranger') ->
  "Hello, #{name}"
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sum = (a, b) ->
  a + b

One thing I like it is, you can be 任性 like this:

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coffee()
coffee("Yo")
coffee "Yo"
coffee("Yo", 2)
coffee "Yo", 2

Array

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storeLocations = ['Orlando', 'Winter Park', 'Sanford']
Can use new lines instead of commas
storeLocations = [
 'Orlando'
 'Winter Park'
 'Sanford'
]

Loop

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storeLocations.forEach (location, index) ->
 alert "Location: #{location}
 
alert "Location: #{location}" for location in storeLocations
for location in storeLocations
 alert "Location: #{location}"

Indent

There are things I don’t like like this.

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coffee =
 name: 'French'
strength: 1

=>

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coffee = {
 name: 'French'
};
({
 strength: 1
})

一行流 (one line combo)

If u do python, you familiar with this.

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filteredFlights =
(flight for flight in currentFlights when stops is '2+' or
flight.routing is 0)

OOP

the great extend keyword
My friend Teddy has a great post about this.

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class Animal
class Snake extends Animal

= >

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// Generated by CoffeeScript 1.8.0
(function() {
  var Animal, Snake,
    __hasProp = {}.hasOwnProperty,
    __extends = function(child, parent) { for (var key in parent) { if (__hasProp.call(parent, key)) child[key] = parent[key]; } function ctor() { this.constructor = child; } ctor.prototype = parent.prototype; child.prototype = new ctor(); child.__super__ = parent.prototype; return child; };
  Animal = (function() {
    function Animal() {}
    return Animal;
  })();
  Snake = (function(_super) {
    __extends(Snake, _super);
    function Snake() {
      return Snake.__super__.constructor.apply(this, arguments);
    }
    return Snake;
  })(Animal);
}).call(this);

TODO

Others

With the character ->, it can lower the possibility of missing braces or brackets.

There’re lots of other stuff, like automatically hoisting for u to check out.

Install

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1. Install Node.js http://nodejs.org/
2. Install npm http://npmjs.org/
3. $ npm install -g coffee-script
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coffee -c test.coffee Creates test.js
coffee -cw test.coffee Every time test.coffee is
updated re-compile.
coffee -c src -o js Compile all .coffee files in the
src dir into the js dir. 
coffee -wc src -o js Every time a file is updated
re-compile

Link:
http://teddy1004.github.io/2014/12/04/class-inheritance-in-JavaScript/
http://coffeescript.codeschool.com/levels/1/challenges/1
http://courseware.codeschool.com/coffeescript_slides.pdf