Boolean primitive query

JavaScript
1

Tell us what’s happening:
Describe your issue in detail here.
I’m not sure why "boolean" passed as true and not any other string value. I typed in "bool", but it did not pass. A non-empty string is truthy, so it seems like it would pass. Does the string "boolean" have any inherent worth that I’m not aware of? Why can’t I just type any string and pass the test. Is there a relation between bool and "boolean" that is inherently truthy?

Thanks as always!

  **Your code so far**


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

}

booWho(null);

  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.93 Safari/537.36

Challenge: Boo who

Link to the challenge:

2

typeof checks what a type of thing is, hence the name. And the type of thing is described in a string – “boolean”, “number”, “string” etc

If you checked if `typeof bool === “random string” it would always be false, because there isn’t a type of thing called “random string”

Always look at the documentation:

3

first of all, here you are not checking whether a value is truthy or not, but checking the value is a boolean, meaning true or false (Here i not meant truthy, bt boolean )

next lets see what is typeof is actually doing

typeof will return the data type of the value given

eg:

typeof 1 will return “number”
typeof “blah” will return “string”
typeof [1,2,3] will return “object”
typeof true will return “boolean”
typeof false will return “boolean”

so what happening in the function is you are checking the value of bool is whether a boolean (true or false not any truthy value)

4

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