js兑现继承机制

function extend(target,parent,params){
	parent.apply(target,params);
	var p = null,o;
	for(p in parent.prototype){
		o = target.constructor.prototype;
		if(!o[p]){
			o[p] = parent.prototype[p];
		}
		o[p]["super"] = parent.prototype;
	}
};

function Person(name){
	this.name = name;
};
Person.prototype.getName = function(){
	alert(this.name);
}
function Student(name){
	extend(this,Person,[name]);
};

var stu = new Student("lynn");
		stu.getName();