CoffeeScript简介

代码从这里CoffeeScript: The beautiful way to write JavaScript抄来的

闲逛博客的时候看到这个东西，以前没听说过，看着挺好玩的，抄点代码，就算是简单介绍吧。

CoffeeScript很小的语言，用好看的方式写js，编译成js代码。项目地址：http://jashkenas.github.com/coffee-script/   

The golden rule of CoffeeScript is: "It's just JavaScript".

下面开始抄代码

CoffeeScript code:

  
    

   
     
    
      

     
       square 
     
       =
     
        (x) 
     
       ->
     
        x 
     
       *
     
        x
cube 
     
       =
     
        (x) 
     
       ->
     
        square(x) 
     
       *
     
        x
    
      


  
    

"Compiled" JavaScript code:

  
    

   
     
    
      

     
       var
     
        cube, square;
square 
     
       =
     
        
     
       function
     
       (x) {
 
     
       return
     
        x 
     
       *
     
        x;
};
cube 
     
       =
     
        
     
       function
     
       (x) {
 
     
       return
     
        square(x) 
     
       *
     
        x;
};
    
      


  
    

ajax

CoffeeScript

  
    

   
     get: (offset, callback, limit) 
   
     =>
   
     
 data 
   
     =
   
     
 project_id: Projects.getCurrent().id
 limit: limit or @default_limit

 
   
     if
   
      offset
 data.offset 
   
     =
   
      Calendar.jsonFormat(offset, 
   
     true
   
     )

 @ajax.getArchived(data, (data) 
   
     =>
   
     
 
   
     if
   
      
   
     !
   
     offset
 @setCache(data)
 callback(data)
 )
  
    

js

  
    

   
     get: 
   
     function
   
     (offset, callback, limit) {
 
   
     var
   
      self 
   
     =
   
      
   
     this
   
     ;

 
   
     var
   
      data 
   
     =
   
      {
 project_id: Projects.getCurrent().id,
 limit: limit 
   
     ||
   
      
   
     this
   
     .default_limit
 }

 
   
     if
   
     (offset)
 data.offset 
   
     =
   
      Calendar.jsonFormat(offset, 
   
     true
   
     );

 
   
     this
   
     .ajax.getArchived(data, 
   
     function
   
     (data) {
 
   
     if
   
     (
   
     !
   
     offset)
 self.setCache(data);
 callback(data);
 });
},
  
    

继承

  
    

   
     class Animal
 constructor: (@name) 
   
     ->
   
     

 move: (meters) 
   
     ->
   
     
 alert @name 
   
     +
   
      
   
     "
   
      moved 
   
     "
   
      
   
     +
   
      meters 
   
     +
   
      
   
     "
   
     m.
   
     "
   
     

class Snake extends Animal
 move: 
   
     ->
   
     
 alert 
   
     "
   
     Slithering...
   
     "
   
     
 super 
   
     5
  
    

一些特性

生成数组

  
    

   
     countdown 
   
     =
   
      (num 
   
     for
   
      num 
   
     in
   
      [
   
     10
   
     ..
   
     1
   
     ])
  
    

string interpolation不知道咋翻译，字符串里放变量

  
    

   
     author 
   
     =
   
      
   
     "
   
     Wittgenstein
   
     "
   
     
quote 
   
     =
   
      
   
     "
   
     A picture is a fact. -- #{ author }
   
     "
  
    

多行字符串

  
    

   
     mobyDick 
   
     =
   
      
   
     "
   
     Call me Ishmael. Some years ago -
never mind how long precisely -- having little
or no money in my purse, and nothing particular...
   
     "
  
    

用@表示this指针

  
    

   
     Account 
   
     =
   
      (customer, cart) 
   
     ->
   
     
 @customer 
   
     =
   
      customer
 @cart 
   
     =
   
      cart

 $(
   
     '
   
     .shopping_cart
   
     '
   
     ).bind(
   
     '
   
     click
   
     '
   
     , (event) 
   
     =>
   
     
 @customer.purchase @cart
 )