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JavaScript JavaScript Foundations Functions Return Values

Jahan Zeb
Jahan Zeb
11,169 Points
Posted by Jahan Zeb
Jahan Zeb
11,169 Points

Can't pass JS code challenge

Hey guys, please help me out passing this code challenge:

http://teamtreehouse.com/library/return-values

This is the code I am using:

function arrayCounter(anArray) {
        if (typeof anArray === "undefined") {
                return 0;
        }
        else if (anArray[0] instanceof anArray){
                return anArray.length;
        }
        else {
                return 0;
        }
}

2 Answers

Riley Hilliard
Riley Hilliard
Courses Plus Student 17,771 Points

You are doing a few things wrong here. First you can make this challenge pass with just an if/else.

The logic is: if the variable type is an array, return the length of the array, else return 0.

When you're checking your instance of an array, you are asking if the first array value is equal to its parent array. You need to check if it is an instance of an "Array".

I wont give you the full answer, but I will get you close enough for you to be able to find your way there:

     function arrayCounter (arr){
        if(/* the arr var is an instance of an Array */){
          return /* the length of the array */;
        } else {
            return 0;
        }
      }
Jahan Zeb
Jahan Zeb
11,169 Points
Jahan Zeb
Jahan Zeb
11,169 Points

Thank a bunch Riley for the hint and making me do it instead! Now I know where I was wrong. 

function arrayCounter (anArray) {
        if (anArray instanceof Array) {
                return anArray.length;
        }
        else {
            return 0;
        }
}

Cheers!