# [X分鐘速成Y](http://learnxinyminutes.com/)
## 其中 Y=coffeescript
源代碼下載：?[coffeescript-cn.coffee](http://learnxinyminutes.com/docs/files/coffeescript-cn.coffee)
CoffeeScript是逐句編譯為JavaScript的一種小型語言，且沒有運行時的解釋器。 作為JavaScript的替代品之一，CoffeeScript旨在編譯人類可讀、美觀優雅且速度不輸原生的代碼， 且編譯后的代碼可以在任何JavaScript運行時正確運行。
參閱?[CoffeeScript官方網站](http://coffeescript.org/)以獲取CoffeeScript的完整教程。
~~~
# CoffeeScript是一種很潮的編程語言，
# 它緊隨眾多現代編程語言的趨勢。
# 因此正如Ruby和Python，CoffeeScript使用井號標記注釋。
###
大段落注釋以此為例，可以被直接編譯為 '/ *' 和 '* /' 包裹的JavaScript代碼。
在繼續之前你需要了解JavaScript的基本概念。
示例中 => 后為編譯后的JavaScript代碼
###
# 賦值:
number = 42 #=> var number = 42;
opposite = true #=> var opposite = true;
# 條件:
number = -42 if opposite #=> if(opposite) { number = -42; }
# 函數:
square = (x) -> x * x #=> var square = function(x) { return x * x; }
fill = (container, liquid = "coffee") ->
"Filling the #{container} with #{liquid}..."
#=>var fill;
#
#fill = function(container, liquid) {
# if (liquid == null) {
# liquid = "coffee";
# }
# return "Filling the " + container + " with " + liquid + "...";
#};
# 區間:
list = [1..5] #=> var list = [1, 2, 3, 4, 5];
# 對象:
math =
root: Math.sqrt
square: square
cube: (x) -> x * square x
#=> var math = {
# "root": Math.sqrt,
# "square": square,
# "cube": function(x) { return x * square(x); }
#}
# Splats:
race = (winner, runners...) ->
print winner, runners
#=>race = function() {
# var runners, winner;
# winner = arguments[0], runners = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
# return print(winner, runners);
#};
# 存在判斷:
alert "I knew it!" if elvis?
#=> if(typeof elvis !== "undefined" && elvis !== null) { alert("I knew it!"); }
# 數組推導:
cubes = (math.cube num for num in list)
#=>cubes = (function() {
# var _i, _len, _results;
# _results = [];
# for (_i = 0, _len = list.length; _i < _len; _i++) {
# num = list[_i];
# _results.push(math.cube(num));
# }
# return _results;
# })();
foods = ['broccoli', 'spinach', 'chocolate']
eat food for food in foods when food isnt 'chocolate'
#=>foods = ['broccoli', 'spinach', 'chocolate'];
#
#for (_k = 0, _len2 = foods.length; _k < _len2; _k++) {
# food = foods[_k];
# if (food !== 'chocolate') {
# eat(food);
# }
#}
~~~
