Question

I’ve seen this in a few places

function fn() {     return +new Date; } 

And I can see that it is returning a timestamp rather than a date object, but I can’t find any documentation on what the plus sign is doing.

Can anyone explain?

Answer 1

That’s the + unary operator. It’s equivalent to:

function(){ return Number(new Date); } 

See http://xkr.us/articles/javascript/unary-add and MDN.