javascript - whta is use of .Class method in ng.core.component in es5 -

var app = ng.core.component({  selector:'myapp', template:'<h1>helloworld</h1>' }). class( { constructor:function() } ); 

according angular2 quickstart guide:

the class method implement component itself, giving properties , methods bind view , whatever behavior appropriate part of ui.

ref: https://angular.io/docs/js/latest/quickstart.html#!#add-the-component-file