I keep getting an 'Oh no' warning on the Javascript identical() task, everytime i submit. Why is this?

Question

I entered my fix in the code section, and clicked submit, but i get no progress or wrong confirmation. Instead i keep getting a pop up warning that something is wrong.

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <title> JavaScript Foundations: Variables</title>
    <style>
      html {
        background: #FAFAFA;
        font-family: sans-serif;
      }
    </style>
    <script src="ignore_this.js"></script>
  </head>
  <body>
    <h1>JavaScript Foundations</h1>
    <h2>Variables: Null and Undefined</h2>

    <div id="container">
    </div>

    <script>

        var myUndefinedVariable = null;
        var myNullVariable = null;

        if(myNullVariable == myUndefinedVariable) {
            identical();
        }

    </script>
  </body>
</html>

Answer 1 · 2015-02-03T05:41:47Z

February 3, 2015 5:41am

Change this:

var myUndefinedVariable = null;

to:

var myUndefinedVariable;  // this variable is now undefined

In your condition, you need to use the 'strict equality' operator (===):

if (myNullVariable === myUndefinedVariable) {
  identical();
}

Because both null and undefined are falsey values the double equality operator (==) returns true; the triple equality operator (===) will check to see if the two values are identical, and in the case of null and undefined they are not 'strictly' the same value, even though they are both falsey.

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rays0

rays0

I keep getting an 'Oh no' warning on the Javascript identical() task, everytime i submit. Why is this?

1 Answer

Clayton Perszyk

Clayton Perszyk

rays0

rays0

Clayton Perszyk

Clayton Perszyk