Create a greeter.ts file:

class Student {    fullname : string;    constructor(public firstname, public middleinitial, public lastname) {        this.fullname = firstname + " " + middleinitial + " " + lastname;    }}interface Person {    firstname: string;    lastname: string;}function greeter(person : Person) {    return "Hello, " + person.firstname + " " + person.lastname;}var user = new Student("Jane", "M.", "User");document.body.innerHTML = greeter(user);

 

 

Webstrom can add watcher to the ts file, it will auto convert to the javascript file.