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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Practice Selecting Elements

Shardul Nandapurkar
Shardul Nandapurkar
969 Points
Posted by Shardul Nandapurkar
Shardul Nandapurkar
969 Points

Strict mode

ReferenceError: Strict mode forbids implicit creation of global property 'i'

js/app.js 
let navigationLinks = document.getElementsByTagName('nav');
for( i = 0; i < navigationLinks; i += 1) {
  navigationLinks[i];
}
let galleryLinks;
let footerImages;
index.html 
<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Nick Pettit | Designer</title>
    <link rel="stylesheet" href="css/normalize.css">
    <link href='http://fonts.googleapis.com/css?family=Changa+One|Open+Sans:400italic,700italic,400,700,800' rel='stylesheet' type='text/css'>
    <link rel="stylesheet" href="css/main.css">
    <link rel="stylesheet" href="css/responsive.css">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
  </head>
  <body>
    <header>
      <a href="index.html" id="logo">
        <h1>Nick Pettit</h1>
        <h2>Designer</h2>
      </a>
      <nav>
        <ul>
          <li><a href="index.html" class="selected">Portfolio</a></li>
          <li><a href="about.html">About</a></li>
          <li><a href="contact.html">Contact</a></li>
        </ul>
      </nav>
    </header>
    <div id="wrapper">
      <section>
        <ul id="gallery">
          <li>
            <a href="img/numbers-01.jpg">
              <img src="img/numbers-01.jpg" alt="">
              <p>Experimentation with color and texture.</p>
            </a>
          </li>
          <li>
            <a href="img/numbers-02.jpg">
              <img src="img/numbers-02.jpg" alt="">
              <p>Playing with blending modes in Photoshop.</p>
            </a>
          </li>
        </ul>
      </section>
      <footer>
        <a href="http://twitter.com/nickrp"><img src="img/twitter-wrap.png" alt="Twitter Logo" class="social-icon"></a>
        <a href="http://facebook.com/nickpettit"><img src="img/facebook-wrap.png" alt="Facebook Logo" class="social-icon"></a>
        <p>&copy; 2016 Nick Pettit.</p>
      </footer>
    </div>
  <script src="js/app.js"></script>
  </body>
</html>
Dale Jones
Dale Jones
9,025 Points
Dale Jones
Dale Jones
9,025 Points

You've forgotten the .length in the for loop.

I believe it should be 

let navigationLinks = document.getElementsByTagName('nav');
for( i = 0; i < navigationLinks.length; i += 1) {
  navigationLinks[i];
}
let galleryLinks;
let footerImages;

1 Answer

paulscanlon
PLUS
paulscanlon
Courses Plus Student 26,735 Points
paulscanlon
paulscanlon
Courses Plus Student 26,735 Points

Hey

In the for loop you need to declare the variable like this.

for(let i = 0; i < navigationLinks; i += 1)

If you don't the variable is automatically declared in the global scope. This is VERY bad practice, but is completely forbidden in "strict mode".

Always declare your variables in the appropriate scope

Happy coding

Paul