Falsy Bouncer - Please explain solution

Falsy Bouncer - Please explain solution
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Please could someone explain to me how the following code works?

function bouncer(arr) {
  return arr.filter(function(item) {
    return item;

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

This passes the Falsy Bouncer challenge, but I don’t understand what part of it is calculating whether or not the ‘item’ is a truthy or falsy if no conditions have been set. I’ve been researching the .filter() method and JS return statements but can’t find an explanation for this.

**Link to the challenge:**


I’ve edited your post for readability. When you enter a code block into the forum, precede it with a line of three backticks and follow it with a line of three backticks to make easier to read. See this post to find the backtick on your keyboard. The “preformatted text” tool in the editor (</>) will also add backticks around text.


Do you understand what “falsy” means? Can you describe it?
Do you understand how filter functions work? Can you describe it?


A falsy value is the equivalent of the boolean expression ‘false’. In the same way that the expression 6 < 7 = false, a falsy value such as (0) inherently = false.

(First time I’ve considered trying to explain this in plain English - I’ll definitely read around this subject to make sure I fully understand it).

The filter method uses a function which sets a condition, and creates a new array from any elements that pass the condition.


Here is the missing piece. A filter function returns a value which is evaluated as a boolean. If the return value is truthy, then the currently-inspected item is kept in the array. If the return value is falsy, the currently-inspected value is removed from the array.


Ah, of course! If no conditions are set then it will just go ahead and filter out truthy values. Brilliant, thanks for your help!