Question

I have just seen this in code

var thisYear = (new Date()).getFullYear();

See it live on JSbin.

This is cool, as I’ve always done something like that in 2 lines, i.e. create the new object instance and assigned it to a variable, then called the method on it.

Is this new method fine to use everywhere? Any gotchas?

Answer 1

That’s not new, but yes it’s safe. You don’t actually need the parentheses either:

new Date().getFullYear();

new Date() and (new Date()) are both expressions that evaluate to a Date object, which you can freely call methods on.

You can even call methods directly on numbers:

(1000).toExponential()

In this case you do need the parens.