原型 prototypal

基于原型的继承相比基于类得继承在概念上更为简单：一个新对象可以继承一个旧对象的属性。

if(typeof Object.beget !== 'function')
{
    Object.beget = function(o)
    {
        var F= function(){};
        F.prototype = o;
        return new F();
    };
}
var myMammal = {
    name: 'Herb the Mammal',
    get_name: function(){return this.name;},
    says: function(){return this.saying || '';}
};

var myCat = Object.beget(myMammal);
myCat.name = 'Hemmal';
myCat.saying = 'meow';
myCat.purr =function(n)
{
    var i, s = '';
    for(i = 0; i < n; i ++)
    {
        if(s)
        {my
            s += '-';
        }
        s += 'r';
    }
    return s;
};
myCat.get_name = function()
{
    return this.says() + ' ' + this.name + ' ' + this.says();
};

函数化 Functional