我们来看看两个代码片段中的两个实现来继承.

>第一个使用augment.js它是Aadit M Shah的脚本
>在这个例子中,我们将使用this script.由Aadit M Shah也是这样做的.

实施1：

var AugmentPerson = Object.augment(function() {
      this.constructor = function(name) {
          this.name = name;
      };
      this.setAddress = function(country,city,street) {
          this.country = country;
          this.city = city;
          this.street = street;
      };
    });
    var AugmentFrenchGuy = AugmentPerson.augment(function(base) {
      this.constructor = function(name) {
          base.constructor.call(this,name);
      };
      this.setAddress = function(city,street) {
          base.setAddress.call(this,"France",street);
      };
    });
    var AugmentParisLover = AugmentFrenchGuy.augment(function(base) {

      this.constructor = function(name) {
          base.constructor.call(this,name);
      };

      this.setAddress = function(street) {
          base.setAddress.call(this,"Paris",street);
      };
    });
    var t = new AugmentParisLover("Mary");
    t.setAddress("CH");
    console.log(t.name,t.country,t.city,t.street); //Mary France Paris CH

在这个例子中,我们使用函数构造函数,而不是直接从对象继承.

实施2：

var CreatePerson = {
        create: function (name) {
            this.name = name;
            return this.extend();
        },setAddress: function(country,street) {
             this.country = country;
             this.city = city;
             this.street = street;
        }
    };
    var CreateFrenchGuy  = CreatePerson.extend({
        create: function (name) {
            return CreatePerson.create.call(this,name);
        },setAddress: function(city,street) {
            CreatePerson.setAddress('France',street);
        }
    });
    var CreateParisLover  = CreateFrenchGuy.extend({
        create: function (name) {
            return CreateFrenchGuy.create.call(this,setAddress: function(street) {
            CreateFrenchGuy.setAddress('Paris',street);
        }
    });

    var t = CreateParisLover.create("Mary");
    t.setAddress("CH");
    console.log(t.name,t.street); //Mary France Paris CH

说实话,我试图看到第二个实现的好处.但我不能.我唯一看到的是更灵活的是因为我们可以使用apply来创建实例：

var t = CreateParisLover.create.apply(CreateParisLover,[“Mary”]);

这给了我们更多的灵活性,这是真的.但是我们可以对this做同样的事情：

Function.prototype.new = function () {
     function functor() { return constructor.apply(this,args); }
     var args = Array.prototype.slice.call(arguments);
     functor.prototype = this.prototype;
     var constructor = this;
     return new functor;
  };

然后我们可以：

var t = AugmentParisLover.new.apply(AugmentParisLover,["Mary"]);

在灵活性,可重用性,难度方面真正的好处是什么？
因为如果你检查两种情况的表现. Object.create()几乎比new：http://jsperf.com/inheritance-using-create-vs-new慢得多
我很混乱

解决方法

var Animal = function Animal(name) {
  this.name = name;
};

Animal.prototype.walk = function walk() {
  console.log(this.name + ' goes for a walk.');
};

var Rabbit = function Rabbit(/* name */) {
  // Because construction and instantiation are conflated,you must call super().
  Animal.prototype.constructor.apply(this,arguments);
};

// Classical inheritance is really built on top of prototypal inheritance:
Rabbit.prototype = Object.create(Animal.prototype);

// Fix the .constructor property:
Rabbit.prototype.constructor = Rabbit;

Rabbit.prototype.jump = function jump() {
  console.log(this.name + ' hops around a bit.');
};

var myRabbit = new Rabbit('Bunny George');

myRabbit.walk();
// Bunny George goes for a walk.

var animalMethods =  {
  walk: function walk() {
    console.log(this.name + ' goes for a walk.');
  }
};

var animal = function animal(name) {
  var instance = Object.create(animalMethods);
  instance.name = name;
  return instance;
};

var rabbitMethods = {
  jump: function jump() {
    console.log(this.name + ' hops around a bit.');
  }
};

var rabbit = function rabbit(name) {
  var proto = rabbitMethods;

  // This is more commonly done like mixin({},animalMethods,rabbitMethods);
  // where mixin = $.extend,_.extend,mout.object.mixIn,etc... It just copies
  // source properties to the destination object (first arg),where properties from
  // the last argument override properties from prevIoUs source arguments.
  proto.walk = animalMethods.walk;
  var instance = Object.create(rabbitMethods);

  // This could just as easily be a functional mixin,// shared with both animal and rabbit.
  instance.name = name;
  return instance;
};

var rabbit2 = rabbit('Bunny Bob');

rabbit2.walk();
// Bunny Bob goes for a walk.

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