Accidental success: Basic Algorithm Scripting - Falsy Bouncer

My code is working ACCIDENTALLY. But I don’t understand why.
What does the function passed inside the filter method do?

function bouncer(arr) {
let x= arr.filter(num=>num)
return x;

bouncer([7, "ate", "", false, 9]);

Challenge: Basic Algorithm Scripting - Falsy Bouncer

Link to the challenge:

I guess MDN article has better explanations than something I can provide

Ask more questions please, if after reading you will still have any.

Filter keeps a value when the callback function returns true/a truthy value, and reject a value when the callback function returns false/a false value

So, depending on what num is (and that is a pretty bad variable name, the values can be anything, not just numbers)…

Thanks for the suggestion for the variable name. I will keep that in mind.

But in this case, if I write


this doesn’t work. Why?

Because not all truthy values are equal to true

Thank you.
I have read it, but failed to understand .

Ow! Now I got it. Thanks a lot for the support.

And I am really sorry if I broke any rules while posting this. This is my first post in the forum.
Thanks again.

Did anyone say anything about breaking rules?

No , nobody said anything about breaking rules.