一个关于js继承的函数

var _extends = (this && this._extends) || (function () {
var extendStatics=Object.setPrototypeOf ||
({proto:[]} instanceof Array && function(d,b){
d.proto=b;
}) ||
function(d,b){
for(var p in b){
if(b.hasOwnProperty(p)){
d[p]=b[p];
}
}
};
return function(d,b){
extendStatics(d,b);
function (){
this.constructor=d;
};
d.prototype= b === null?Object.create(b):((.prototype=b.prototype),new __());
}

})();

var Dialog = (function (_super) {
__extends(Dialog, _super);
function Dialog(){

};
Dialog.prototype.init=function(){

};
return Dialog;

})(_super);