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  • js继承

    function Animal(){

    }

    function Cat(){ 

      Animal.call(this);

    }

    function extend(Parent, Child){

      var F = function(){};

      F.prototype = Parent.prototype;

      Child.prototype = new F();

      Child.prototype.constructor = Child;

      Child.super = Parent.prototype;

    }

    console.log(Object.contructor == Function); //true

    console.log(String.contructor == Function); //true

    console.log(Function.contructor == Function); //true

    function Foo(){}

    var bar = {};

    var a = new Foo();

    console.log("bar.constructor : " + bar.constructor);
    console.log("bar.prototype : " + bar.prototype);
    console.log("bar.__proto__ : " + bar.__proto__);

    console.log("a.constructor : " + a.constructor);
    console.log("a.prototype : " + a.prototype);
    console.log("a.__proto__ : " + a.__proto__);

    console.log("Foo.constructor : " + Foo.constructor);
    console.log("Foo.prototype : " + Foo.prototype);
    console.log("Foo.__proto__ : " + Foo.__proto__);

    console.log("Function.constructor : " + Function.constructor);
    console.log("Function.prototype : " + Function.prototype);
    console.log("Function.__proto__ : " + Function.__proto__);

    console.log("Object.constructor : " + Object.constructor);
    console.log("Object.prototype : " + Object.prototype);
    console.log("Object.__proto__ : " + Object.__proto__);

    先有的Object.prototype, Object.prototype构造出Function.prototype,然后Function.prototype构造出Object和Function。
    Object.prototype是鸡,Object和Function都是蛋。

    https://www.zhihu.com/question/35442532

    http://blog.csdn.net/tom_221x/article/details/5316675

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  • 原文地址:https://www.cnblogs.com/ftxc/p/8516416.html
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