This week Microsoft released its shiny new JavaScript pre-processor - TypeScript. It represents a superset of JavaScript that is designed for large-scale application development. It utilizes concepts that most developers are comfortable with in their non JavaScript languages. Things like Classes, Modules, and Type checking.

These are all things that many people complain that JavaScript does not have built in.  With TypeScript, JavaScript does not magically gain these things. TypeScript makes these things accessible to a developer through its pre processing. Developers and JavaScript do not need TypeScript, and it is not a requirement to build large scale applications. It won't magically make crappy programming better, but it may help catch a gotcha for someone every now and again, just as JSHint would. I for one think that it will take off rather well, especially in the ASP.Net community. I also will probably try it out in a project or two or three. I like that it looks and feels like JavaScript, which is a syntax that I am comfortable with.  That is one reason why I have not adopted CoffeeScript, it just looks so foreign to me. I suppose if I were a full time Ruby on Rails developer, CoffeeScript would feel right, but I'm not, so it doesn't.

I'm going to end this by just showing the difference between TypeScript and JavaScript. It is subtle and that is appealing to me. See the comparisons below:

// TypeScript
class Greeter {
	greeting: string;
	constructor (message: string) {
		this.greeting = message;
	}
	greet() {
		return "Hello, " + this.greeting;
	}
}   
 
var greeter = new Greeter("world");
 
var button = document.createElement('button')
button.innerText = "Say Hello"
button.onclick = function() {
	alert(greeter.greet())
}
 
document.body.appendChild(button);

// JavaScript
var Greeter = (function () {
    function Greeter(message) {
        this.greeting = message;
    }
    Greeter.prototype.greet = function () {
        return "Hello, " + this.greeting;
    };
    return Greeter;
})();
var greeter = new Greeter("world");
var button = document.createElement('button');
button.innerText = "Say Hello";
button.onclick = function () {
    alert(greeter.greet());
};
document.body.appendChild(button);