JS组合模式

[javascript]
function Macbook() { 
    this.cost = function () { 
        return 1000; 
    }; 
} 
 
function Memory(macbook) { 
    this.cost = function () { 
        return macbook.cost() + 75; 
    }; 
} 
 
function BlurayDrive(macbook) { 
    this.cost = function () { 
        return macbook.cost() + 300; 
    }; 
} 
 
 
function Insurance(macbook) { 
    this.cost = function () { 
        return macbook.cost() + 250; 
    }; 
} 
 
 
// 用法 
var myMacbook = new Insurance(new BlurayDrive(new Memory(new Macbook()))); 
console.log(myMacbook.cost()); 



摘自 PainsOnline的专栏