I have not used TypeScript, so can anyone explain to me what is the difference between the above the normal JavaScript code like this:

    function myFunction(x) {
        if (x === null) { 
            return;
        }

        console.log(x + 1); // x is now a number
    }

Edit: Or is this example being used to show that TypeScript now support multiple types including null in the parameter?

I assumed that such feature would be available by default.