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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Create a Two Dimensional Array

Jason Vines
Jason Vines
5,207 Points
Posted by Jason Vines
Jason Vines
5,207 Points

JS Loops, Arrays & Objects not recognizing legitimate code...again.

It's probably another peculiarity with the Treehouse site but I have a Challenge Task that doesn't like my answer but that answer will work in the console of a web browser. Somebody tell me what the site is looking for that I can't see.

script.js 
var coordinates = [
  [24, 36],
  [48, 52],
  [66, 09],
  [33, 18]
];
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Objects</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

Joe Beltramo
Joe Beltramo
Courses Plus Student 22,191 Points

This shouldn't work in any system? Anyway, structurally you are correct. The issue here is the numbers you provided. The JavaScript compiler has no idea what 09 is, remove the zero in front of the 9 and give that a shot.

Jason Vines
Jason Vines
5,207 Points
Jason Vines
Jason Vines
5,207 Points

Thanks for the help on this. It's always the little things isn't it but it was recognized in the console.log I printed in Chrome and it dropped the 0 and still listed the array.

Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi Jason,

When you put a leading zero on a number like that then it gets interpreted as an octal number. Octal is base 8 so it only uses the digits 0-7.

09 would not be a valid octal number. The chrome console does not issue an error for this but in the firefox console you get the following error:

SyntaxError: 09 is not a legal ECMA-262 octal constant

I'm guessing that the challenge checker is catching this error as well which is why you couldn't pass.

If you had used 07 instead then you would have passed the challenge because that would be a valid octal number.