Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript jQuery Basics Understanding jQuery Events and DOM Traversal DOM Traversal with jQuery

Kenneth Dubroff
Kenneth Dubroff
10,612 Points
Posted by Kenneth Dubroff
Kenneth Dubroff
10,612 Points

$(‘li’).eq(-2) Unexpected AST node type encountered initializing the jQueryMethodCall.arguments property: UnaryExpressio

Given the following html:

<!DOCTYPE html>
<html lang="en">
<head>
    <title>Document</title>
</head>
<body>
  <h2>Student List</h2>

  <ul class="student-list">
    <li>James McAvoy</li>
    <li>Alena Holligan</li>
    <li>Wade Christensen</li>
    <li>Matt Krzyzynski</li>
  </ul>

  <script src="jquery-3.2.1.min.js"></script>
  <script src="app.js"></script>
</body>
</html>

Using console, I'm able to select Wade Christensen with:

$('li').eq(-2);

Why is this throwing an error in the Teamtreehouse editor, but not on localhost?

1 Answer

Kuanyshbek Ospanov
Kuanyshbek Ospanov
17,416 Points
Kuanyshbek Ospanov
Kuanyshbek Ospanov
17,416 Points

About first task. Firstly read documentation about ".eq() method": https://www.w3schools.com/jquery/traversing_eq.asp

$('li').eq(2);

About second task. Again I recommend you read documentation about this methods at: https://www.w3schools.com/jquery/jquery_ref_traversing.asp

$('li').eq(2).prev().prev();
Kenneth Dubroff
Kenneth Dubroff
10,612 Points
Kenneth Dubroff
Kenneth Dubroff
10,612 Points

Oops, it was -1 in console, which probably works here as well since it's mentioned in the video that you can traverse in reverse