A better description.

Thank you very much for your reply ;)

It's a bitwise OR operator which in this case (against 0) essentially cuts of all non integers. Here it's used as a somewhat crude and hacky way to avoid Math.floor() or parseInt().

My advise would be to be careful using it in your projects. The | 0 is easily overlooked and can leave your future you searching forever where your math doesn't add up. Math.floor() does a better job at being self-explanatory. Since the example above is very short, the | 0 doesn't hurt for the simple purpose it serves.

Also look at stanleyvarga's comment. He also makes a solid point not to use it everywhere.

What means this "|" in Javascript ?

Very nice. Not unique values, but realy nice!

Alr raised as issue

in the following format of date: YYYY/MM/DD.

I think YYYY/MM/DD is pretty clear. I've updated the test cases to only generate 4 digits years.

Nice trick, thanks.

With backticks you can.

I didn't know you can ommit the parentheses

It's a;r added some time ago

Nice One!