inherit继承模式

                function Father () {

                }
                Father.prototype.lastName = "Zhang";
                function Son () {

                }
                Son.prototype = Father.prototype;
                
                function F () {}
                function inherit (Target, Origin) {
                    Target.prototype = Origin.prototype;
                }
                inherit(F, Father);
                Son.prototype = new F ();
                Son.prototype.name = "zhuqi";
                var son = new Son();
                var father = new Father ();

优化之后的版本：                function Father () {

                }
                Father.prototype.lastName = "Zhang";
                function Son () {

                }
                
                function inherit (Target, Origin) {
                    function F () {}
                    F.prototype = Origin.prototype;
                    Target.prototype = new F();
　　　　　　　　　　　　Target.prototype.constuctor = Target;

                }
                inherit(Son, Father);
                Son.prototype.name = "zhuqi";
                var son = new Son();
                var father = new Father ();

把F当作空的构造对象，此继承模式为衍生发展下来的‘圣杯模式’。其余的继承会发生一个问题，如：给Son的prototype增加属性会连带Father一起增加。

注：inherit函数中应再加一句：Target.prototype.constuctor = Target                  因为继承的原因，Son的constructor会在Son.__proto__中找，找到的是F.__proto__，但是F.__proto__又是继承自Father,因此

Son的constructor会指向father。所以应当加一句