Checking for NaN falsy value

I’m not asking for help. I’m just pointing out that it would be nice if somewhere in the Hints we were informed that NaN is unique in that some methods, such as indexOf cannot find NaN.

function bouncer(arr) {
return arr;
}

bouncer([7, "ate", "", false, 9]);
  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:85.0) Gecko/20100101 Firefox/85.0.

Challenge: Falsy Bouncer

Link to the challenge:

In this challenge you need to use the idea of falsy instead of trying to search for some special values to remove. A value is falsy if it “acts like” false when used as a logical condition:

if (NaN)
  console.log("NaN is *not* falsy!");

I wouldn’t look at anything that compares a value to NaN or any other particularly falsy value.


I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

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console.log(NaN === NaN) //false
//NaN is not strictly equal to NaN so something that uses 
//strict equality like indexOf will not work

//Things you can do to check wether something is falsely or not
//is either by using the Boolean constructor or the not operator

console.log(Boolean(NaN)) //false

console.log(!NaN) //true, Its the “not” operator and
/// “NaN” is not “true”  so thats what it returns

console.log(!!NaN) //true, logically is “true”

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