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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Using Array Methods

not sure on the final output

not sure what the challenge is looking for

var months = ['January','February','March','April','May','June','July','August','September','October','November','December'];
<!DOCTYPE html>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
<script src="script.js"></script>

2 Answers

So this code challenge is asking you to replace the array in the months variable with a string using the join method. The string should include the months separated by a comma and a space, so we pass ', ' in as an argument of the join method. We then to print that string out to the console.


var months = ['January','February','March','April','May','June','July','August','September','October','November','December'];
months = months.join(', ');

It's probably not best practice to go replacing an whole array with a string, if this was a const variable, we'd get an error. Ideally, we would create a new variable when concatenating the months array. But hey, this is what the code challenge is asking for, so who am I to argue!

Hi Berian,

Thanks. I tried the update and now I get this error:

TypeError: 'undefined' is not a function (evaluating 'months.join(", ")')

What do you think?


Ahh so reading the task again, my initial thought on replacing the array was correct. It's not really clear in the instructions, but it actually wants you to create a new variable called final. Let's use const variables here to ensure that nothing is going to be replaced that we don't want to:

const months = ['January','February','March','April','May','June','July','August','September','October','November','December'];
const final = months.join(', ');