freeCodeCamp/guide/english/certifications/javascript-algorithms-and-data-structures/basic-algorithm-scripting/boo-who/index.md

title

title
Boo Who

Boo Who

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Problem Explanation

This program is very simple, the trick is to understand what a boolean primitive is. The programs requires a true or false answer.

Relevant Links

• Boolean

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Hints

Hint 1

You will need to check for the type of the parameter to see if it is a boolean.

Hint 2

To check for the type of a parameter, you can use typeof.

Hint 3

Since you must return true or false you can use if statements or just have it return the boolean used for the if statement.

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Solutions

Solution 1 (Click to Show/Hide)

function booWho(bool) {
  return typeof bool === "boolean";
}

// test here
booWho(null);

Code Explanation

• Uses the operator typeof to check if the variable is a boolean. If it is, it will return true. Otherwise, if it is any other type it will return false.

Relevant Links

• typeof